Double Loop Podcast: Recent Episodes
Glenn Langenburg and Eric Ray
Whether you're a practicing Latent Print Examiner or you're interested in forensics and true crime, the Double Loop Podcast is a weekly show featuring Glenn Langenburg and Eric Ray discussing latent print topics, current events in forensic science, the newest research articles, interesting guests, and analysis of notable cases from a forensic scientist perspective.
Just 60:128-135). https://doi.org/10.1016/j.scijus.2019.09.008Cale, C.M., et al. (2016) Could Secondary DNA Transfer Falsely Place Someone at the Scene of a Crime? J For Sci 2016; 61(1): 196-203 doi: 10.1111/1556-4029.12894.
Eric and Glenn finish this two-parter episode about ASB Standards and Best Practice Recommendations. Specifically, in Part 2, they cover ASB Standard 015 "Standard for Examining Friction Ridge Impressions" (2024) and ASB Best Practice Recommendation 166 "Best Practice Recommendation for Comparison and Evaluation of Friction Ridge Impressions" (2024). The guys discuss how to use the standards, their own experiences, some of the critical requirements and recommendations, etc.ASB Standard 015, First Edition 2024 Standard for Examining Friction Ridge Impressionshttps://www.aafs.org/sites/default/files/media/documents/015_Std_e1.pdfASB Best Practice Recommendation 166, First Edition 2024 Best Practice Recommendation for Comparison and Evaluation of Friction Ridge Impressionshttps://www.aafs.org/sites/default/files/media/documents/166_BPR_e1.pdf
Eric and Glenn start off this supersized two-parter topic with a Regional Quirkisms game of Canadian-isms. Then they move past the Great White North and talk about ASB Standards and Best Practice Recommendations. Specifically, they cover ASB Standard 015 "Standard for Examining Friction Ridge Impressions" (2024) and in Part 1, cover ASB Best Practice Recommendation 165 "Best Practice Recommendation for Analysis of Friction Ridge Impressions" (2024). The guys discuss how to use the standards, their own experiences, some of the critical requirements and recommendations, etc.ASB Standard 015, First Edition 2024 Standard for Examining Friction Ridge Impressions https://www.aafs.org/sites/default/files/media/documents/015_Std_e1.pdfASB Best Practice Recommendation 165, First Edition 2024 https://www.aafs.org/sites/default/files/media/documents/165_BPR_e1.pdf
Eric and Glenn start the episode with a listener email and then play a numbers themed game of Regional Quirkisms. For the topic of this episode, the guys discuss a 2025 paper from Simon Cole and Justin Sola titled "First impressions matter: Mundane obstacles to a forensic device for probabilistic reporting in fingerprint analysis". The article discusses practical and realistic obstacles and hurdles to developing a validated, accepted, and commercially-available statistical model for fingerprint evidence. The article takes the novel view that most sources cite either "practitioner disinterest" (or worse: practitioner rejection) or lack of push and influence from the Courts, Daubert challenges, or Authoritative bodies. However, once you remove those two obstacles and assume examiner 'buy-in' and Courts pushing for empirical data over subjective examiner expertise, what 'mundane' obstacles exist that most people don't realize or think about? The article discusses a number of surprising, non-trivial obstacles that have a huge influence on the state of statistical model development in the field today.Article:Cole, S.A.; Sola, J.L. First impressions matter: Mundane obstacles to a forensic device for probabilistic reporting in fingerprint analysis. Social Studies of Science (2025), 55(5): 683-710.https://doi.org/10.1177/03063127251333074
Management: An International Journal, 5(1–2), 15–37. https://doi.org/10.1080/19409044.2014.929759
Glenn Langenburg and Eric Ray interview Angela Tonietto about her recent article on the frequency of patterns in palm prints. ("Patterning in the Distal Portions of the Palms as a Key to Palm Print Identification". 2025, 75-3, p.274.) The research analyzes the frequency of loops and deltas in the interdigital area and compares the results to past research. (Link mentioned in episode: https://demo.hugin.com/example/FingerprintEvidence)
Happy New Year 2026! The boys are back in town, with a new game: Regional Quirkisms. After discussing Minnesota quirkisms, the guys answer a listener question from Ireland: "What's the most number of corresponding minutiae that you have seen from two impressions from different sources?". This leads to a deep dive on close non-matches. The guys share their tips, tricks, and red flag warnings for dealing with close non-matches. They discuss a few examples and talk about the relevant research on this topic.
Eric Ray and Glenn Langenburg talk about their week in Orlando at the 2025 IAI Educational Conference. Hear about Quality Metrics, limited examinations, and linking cases together, and hear from some of the conference attendees.
In this episode Eric poses to Glenn a Mandela effect question concerning household cleaning products. After that, the guys celebrate the 4th of July holiday by welcoming their guests from Ireland. Four fingerprint examiners from Forensic Science Ireland (FSI), the national forensic lab in Ireland, join the podcast. The guests are Dr. Aoife Power, Dr. Craig Mullen, Mr. Columb Doherty, and Dr. Kim Connick. Glenn and the guests talk about their time at the recent European Academy of Forensic Science (EAFS) conference in Dublin in May 2025. The examiners from FSI discuss their research, posters, and presentations from EAFS. Eric is also curious about their new AFIS system and has lots of questions about their processes. The guests discuss forensic fingerprint practices in Ireland and especially working in their new national laboratory.Forensic Science Ireland: https://forensicscience.ie/Dr. Kim Connick: kconnick@fsi.gov.ie
In this episode, the guys start with a product-based Mandela effect question. Then they welcome back long-time friend of the show and webmaster, Michael Whyte from the New South Wales police force in Australia. Michael has a question for Glenn and Eric, regarding latent-to-latent comparisons, using latent prints as 'proxy exemplars' when the exemplars are worse than the latent prints or incomplete, and various off-shoots of these questions. The guys discuss the theoretical basis and some of the legal issues that arise in both the U.S. and Australia.
In this episode, Eric stumps Glenn with a geography based Mandela Effect question. Then the guys welcome their guest commentator, Brendan Max, Public Defender and Chief of the Forensic Science Division in Chicago, Illinois. Eric, Glenn, and Brendan take a second look at the 2025 FBI/Noblis follow-up black box study for latent fingerprints. The guys had previously done a cursory review of the paper in Episode 282, and now wanted to dig in a bit into the appendices and take another look at some trends. Brendan offers his insights and shows that he’s pretty proficient with a spreadsheet too! The guys go back and forth discussing the strengths and limitations of the study and where the methodology and practice has likely improved since the original Black Box study (conducted in 2009).Article is available for free at:doi.org/10.1016/j.forsciint.2025.112457
Glenn Langenburg and Eric Ray review two articles from Cell that focus on the genetic basis for ridge development and pattern formation. 'The developmental basis of fingerprint pattern formation and variation' by Glover, et al., and 'Limb development genes underlie variation in human fingerprint patterns' by Li, et al. Our understanding of these complex processes continues to grow, and these papers further support our field and our conclusions.
In this episode, Glenn and Eric start with a quick game of “A Truth, A Lie, and a Mandella Effect”. Then they pose a question from a listener regarding interest in a forum where listeners can go and discuss the episodes of the show, ask questions, and chat “amongst themselves”. Finally they get to the long awaited Noblis/FBI study “Black Box 2” latent fingerprint error rate study. This is a re-do of the 2011 black box study for latent fingerprint performance. This study “Accuracy and reproducibility of latent print decisions on comparisons from searches of an automated fingerprint identification system” by Hicklin, Richetelli, Taylor and Buscaglia (For Sci Intl, 370 (2025), 112457), reported the performance of 156 U.S. latent print examiner participants each reviewing about 100 latent prints/comparisons resulting in over 14,000 trials. The study reports numerous statistics of performance such as sensitivity (63%), specificity (70%), false positive error rate (0.2%), and false negative error rate (4.2%). The guys also discuss some important study design differences, plus there are a lot of data in the appendices. Finally they talk about the number of false positives made in the study (n=23) and the fact that 13 of those 23 were made by one participant and how that impacted the results.Article is available for free at:https://doi.org/10.1016/j.forsciint.2025.112457
Eric Ray and Glenn Langenburg pay tribute to our colleague and friend. Kasey Wertheim passed away on March 7, 2025 and will be greatly missed. Please join us as we remember his legacy and contributions to the field of fingerprints and tell a few personal stories.
Eric Ray and Glenn Langenburg pay tribute to our mentor and friend. Pat Wertheim recently passed and will be greatly missed. Please join us as we remember his legacy and tell a few stories.
In this episode Glenn and Eric catch up after some hectic travel from recent weather issues. They do some news updates and also Eric had advice for new Patreon subscribers. Then they play an Oscar-themed round of “A Truth, a Lie, and a Mandela Effect” because it is the weekend of the 2025 Oscars. Then the guys tackle a topic which has come up many times in the past, but they’ve never actually dived into before: Simultaneous Impressions. They talk about different scenarios that can occur such as: some impressions stand alone, none stand alone, aggregation of features, and physical gaps or voids in an impression. They review the famous Mass v. Patterson case from 2005 that started the initial controversy in the field. They also have a chance to discuss John Black’s JFI research article from 2006 and other source material on the subject.Reference:Black, J.P. Pilot Study: The Application of ACE-V to Simultaneous (Cluster) Impressions. Journal of Forensic Identification, 56(6) Dated: November/December 2006 Pages: 933-971.
In this first recorded episode of 2025, Eric and Glenn start with Eric being pedantic in his “A Truth, A Lie, and a Mandela Effect”. The guys catch up on New Year stuff and then launch into a review of a research paper from New South Wales, Australia, titled “How often do fingerprint examiners disagree in routine casework?” by O’Connor and Chapman (2024) from Forensic Science International. Eric first discusses some of the important differences in casework workflow and conclusions between Aussie examiners and U.S. examiners. Then they discuss the results of the paper and the significance of the findings. At the end, they discuss solutions and ideas for resolving conflict and ultimately find that conflicting results and examiner disagreements are a normal, expected, natural part of the examination process.Find the paper at: https://doi.org/10.1016/j.forsciint.2024.112139
Glenn and Eric interview Sarah Chu, director of policy and reform with the Perlmutter Center for Legal Justice's (PCLJ) forensic science policy initiatives. Sarah breaks down her doctoral thesis on quality management and oversight in forensic science laboratories.
In this episode the guys discuss historical figures in the field of fingerprints. At the top of the episode Eric gives Glenn an Australian themed “A Truth, a Lie, and a Mandela Effect”. Glenn tells a couple of stories from his trip to London, which also inspired the topic for the episode. Because of Glenn’s time in Switzerland this fall reading old texts, he learned a lot about the early days of fingerprints. The guys discuss contributions, stories and cases from Juan Vucetich, Sir Francis Galton, Sir Henry Faulds, Sir Edward Henry, Alphonse Bertillon, Dr. Edmond Locard, and more!
The guys start out with a quick explanation of why Glenn’s sound is so bad (he’s in Switzerland recording). They also start the new “season”, post-IAI with a new game: "Truth, Lie, or Mandela Effect?" Eric talks about his fall conference junket and then the guys finally catch up on the IAI. They discuss their favorite lectures, workshops, and activities at the 2024 IAI Conference in Reno, NV. They summarize some of their standout lectures that they attended. Glenn then discusses how the Double Loop Podcast vendor booth went with Rebecca Coutant running it during the conference. Rebecca also was “Our Girl Friday”, doing her impromptu interviews with conference attendees.
Eric and Glenn are back from a little summer break, prepping for the 2024 IAI Conference in Reno. They do a final “Where in the Whorld?” game. Then they jump into a recent paper on “Inconclusive” decisions (Swofford, et al. (2024) “Inconclusive Decisions and Error Rates in Forensic Science”, Forensic Science International: Synergy (vol 8; 100472)) authored by several members of NIST. The paper proposes a method for computing and communicating error rates when “inconclusive” decisions are made. The paper also focuses on making clear distinctions between “method performance” versus “method conformance”. The guys discuss their views on the method and the implications the paper may have for fingerprint examiners and their agencies.Swofford, H. , Lund, S. , Iyer, H. , Butler, J. , Soons, J. , Thompson, R. , Desiderio, V. , Jones, J. and Ramotowski, R. (2024), Inconclusive Decisions and Error Rates in Forensic Science, Forensic Science International: Synergy, [online], https://doi.org/10.1016/j.fsisyn.2024.100472, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=957335 (Accessed August 31, 2024)Link to open source paper here: https://doi.org/10.1016/j.fsisyn.2024.100472
Glenn and Eric are joined by Angela Hilliard to discuss her experiences with a cold case from the Pacific Northwest. Genetic genealogy provided a suspect's name from a cold case double homicide, and a latent palm print was left on the victim's van. Angela walks us through her initial erroneous exclusion, the subsequent identification, court testimony, and the resulting press coverage. A must-listen episode for examiners on how to handle erroneous conclusions, even in high-profile cases. (Apologies for the audio in this episode. We did not realize until later that some of audio was poorer quality than normal.)
This super-sized episode has the guys interviewing several people from a recent Expert Working Group on Human Factors in the discipline of DNA. Glenn starts by giving Eric his “Where in the Whorld” question and they catch up on some recent travels. Glenn also explains why this episode does NOT feature a continuation of the previous episode on the Peacemaker case, but instead pivots to a different DNA topic. In May 2024, NIJ/NIST released a Human Factors and Forensic DNA Interpretation report. (The) Niki Osborne, Ph.D., the project lead and contractor for NIST (Natl Institute of Standards and Technology) describes how the project came to be and how NIST selected the Expert Working Group (EWG). Then, two members of the EWG, Jarrah Kennedy, Assistant DNA Supervisor, Kansas City Police Crime Laboratory, and Michelle Madrid, DNA Technical Leader, Los Angeles County Sheriff’s Department, discuss the various recommendations in the report. The group covers all sorts of fun topics within DNA discipline such bias, new software and computational approaches, activity level, implementation, enforcement, and so forth. The episode ends with Niki and Glenn discussing other disciplines and future reports.Links to the free report:Expert Working Group on Human Factors in Forensic DNA Interpretation (May 2024). Forensic DNA Interpretation and Human Factors: Improving Practice Through a Systems Approach. National Institute of Standards and Technology, Gaithersburg, MD, NIST IR 8503. http://doi.org/10.6028/NIST.IR.8503https://nvlpubs.nist.gov/nistpubs/ir/2024/NIST.IR.8503.pdfGuests:Nikola Osborne, Ph.D., NIST Contractor, and Project Lead for the Expert Working Group.Jarrah Kennedy, Assistant DNA Supervisor, Kansas City Police Crime LaboratoryMichelle Madrid, DNA Technical Leader, Los Angeles County Sheriff’s Department
Eric and Glenn start the episode with a Where in the Whorld that leads to a little catching up. Glenn was in NYC recently (saw the Harry Potter show on Broadway, indulging his “magician” side) and Eric has been doing the conference circuit. Eric is also soliciting fingerprint experts for a research project on ‘estimating image resolution’ based on ridge density. The guys also got a listener voicemail that they discuss (and roundly disagree with). Finally they discuss the main topic for the show, a homicide case and trial that Glenn testified in: South Dakota v. Jeremiah Peacemaker. Glenn covers his involvement and the fingerprint evidence. In the second half of the show, the guys welcome Anjali Ranadive, who was the DNA expert for the defense, to discuss the DNA evidence and testimony in the case. Both Anjali and Glenn had an opportunity to witness the DNA testimony at trial and were astounded by the “scientific conclusions” drawn, and testified to, by the DNA analyst.Contact Anjali Ranadive: scilawforensics@aol.comDay 1 of Trialhttps://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-one/article_74b84328-d515-11ee-a210-8b7ef07e2631.htmlDay 2 of Trialhttps://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-two/article_eb1531e4-d5e6-11ee-ac1c-f39cc7b07d9e.htmlDay 3 of Trialhttps://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-three/article_6a7c27f2-d6b5-11ee-9124-3f5cf33a83bb.html#:~:text=The%20verdict%20is%20in%2C%20Jeremiah,on%20all%20counts%20of%20murderDay 4 of Trialhttps://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-four---state-rests-its-case/article_46573850-d780-11ee-a368-573401987ead.htmlDay 5 of Trialhttps://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-five/article_a1c7fbf2-d85c-11ee-8ef5-ef34bb7cdee9.htmlDay 6 of Trialhttps://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-six/article_29b37812-daa5-11ee-912e-9bf06a02bb89.htmlDay 7 of Trial (Final Day)https://www.mykxlg.com/news/local/murder-trial-of-jeremiah-peacemaker-day-seven---the-jury-is-out/article_b078ec24-db5e-11ee-bcfb-7b2eb5a1c73b.htmlVerdict Announcedhttps://www.mykxlg.com/news/local/the-verdict-is-in-jeremiah-peacemaker-is-found-not-guilty-on-all-counts-of-murder/article_85ff1e54-db7d-11ee-b58d-27963af509b4.htmlhttps://www.dakotanewsnow.com/2024/03/05/jeremiah-peacemaker-found-not-guilty-death-kendra-owen/
Today Eric and Glenn finish Part 2 on the 2023 Report of the Texas Forensic Science Commission dealing with a latent print case. They continue to discuss the TFSC report that followed an investigation into a complaint filed against the latent print contractor(s) in the Joseph Webster case. In part 2, the guys focus on Glenn's examination which concluded that the Webster palm mark was a complex mark and that 3 critical things will shape the conclusion rendered by an examiner: 1) which images were used; 2) which features were relied upon; 3) how the examiner applied the ACE-V methodology. Finally, they discuss the over 2 dozen recommendations that the Commission made for fingerprint examiners in Texas to follow in latent print examinations.www.txcourts.gov/media/1457617/fi…-as-of-12623.pdf
Today Eric and Glenn start Part 1 of a two-parter on the 2023 Report of the Texas Forensic Science Commission dealing with a latent print case. First the guys do some catching up and play Where in the Whorld. They also discuss an email from Simon Cole and inquire on the impact of the recent AI paper on fingerprints. Then they discuss the TFSC report that followed an investigation into a complaint filed against the latent print contractor(s) in the Joseph Webster case. The webster case was a homicide cold case that eventually broke with a CODIS hit and a subsequent apparent bloody palm print at the scene of the crime. Initially the palm print was not identified to Webster, but then after the CODIS hit occurred to Webster and a second person, the latent print evidence was re-visited in 2013, and an identification was declared (pursuant to reviewing additional palm print exemplars of Webster). Testimony occurred in 2016 by a project manager, but not any of the original examiners. In 2020, a contractor for the defense was hired to review the case and several examiners were unable to verify the identification. This conflict, as well as a review of the testimony, sparked a complaint to the TFSC in the case. The guys review the facts and details of the case in Part 1.Link to TFSC Reporthttps://www.txcourts.gov/media/1457617/fir-complaint-2216-rsa-latent-prints-as-of-12623.pdf
Eric Ray and Glenn Langenburg sit down for a chat with Steve Johnson about face examiners, face comparisons, and the IAI. Steve's background includes latent prints, forensic art, face comparison, crime scene, and many positions with the IAI. He shares the future of the face discipline and how the IAI is working towards a certification process.
Eric and Glenn host another guest from Australia in today’s episode. After another round of Where in the Whorld and a few stories from Eric’s childhood, the guys welcome Chloe George from New South Wales Police Force, Australia. Glenn saw Chloe present at IAFS, where her presentation on phalange pattern classification won best Oral (Presentation). Chloe introduces a system of phalange pattern classification first described by Marie Ploetz-Radmann in 1937. She walks us through the system and the 12 general pattern types in phalanges and then also shares her personal data and testing that she performed.A copy of her IAFS presentation can be found here:https://docs.google.com/presentation/d/1yrUsOFM5alJV1rQcrTGXiQkDb-3DuWUO/edit#slide=id.p5
In this post-New Year’s Eve 2023-2024 episode, the guys start by discussing their New Year’s Eve and play another round of Where in the Whorld. They then introduce their guest from the New South Wales Police Force, Andrew Chapman. Glenn had the benefit of seeing Andy’s presentation at IAFS in Sydney. Andy presented on a fingerprint black box error rate study conducted with laypeople, trainees, and experts in New South Wales, Australia. The guys discuss various statistics in the study, especially when comparing across the participant groups. The Aussie data are very similar to U.S. examiner data and the guys draw some parallels to other research. The guys also discuss some novel aspects to the study design that make this one such a fascinating study.
Glenn and Eric start by talking about their Christmas plans, followed by a game of “Where in the Whorld”. They then welcome their guest, Dr. Bethany Growns, a lecturer and psychologist at the University of Canterbury, in New Zealand. Bethany joins the show to discuss her research on matchers, super-matchers, and research she has conducted with novices (lay people), fingerprint, firearms, and facial recognition experts. She discusses the advantages of natural ability v. trained expertise and how it impacts one’s ability to perform matching tasks in the expert’s domain v. other domains. The guys ask questions about how to utilize this research to impact training programs. Finally, they discuss more aspects of the IAFS conference where Glenn met Bethany.Growns B, Dunn JD, Mattijssen EJAT, Quigley-McBride A, Towler A. Match me if you can: Evidence for a domain-general visual comparison ability. Psychon Bull Rev. 2022 Jun;29(3):866-881. doi: 10.3758/s13423-021-02044-2. Epub 2022 Jan 7. PMID: 34997551; PMCID: PMC9166871.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9166871/Other publications by Growns https://www.bethanygrowns.com/publicationsAre you a super-matcher? Test your skills!Sign up to participate in studies by Dr. Growns:https://canterbury.qualtrics.com/jfe/form/SV_038MorkGlc9SDoW
Eric and Glenn respond to the recent allegations that a computer science undergraduate at Columbia University, using Artificial Intelligence, has “proven that fingerprints aren’t unique” or at least…that’s how the media is mischaracterizing a new published paper by Guo, et al. The guys dissect the actual publication (“Unveiling intra-person fingerprint similarity via deep contrastive learning” in Science Advances, 2024 by Gabe Guo, et al.). They state very clearly what the paper actually does show, which is a far cry from the headlines and even public dissemination originating from Columbia University and the author. The guys talk about some of the important limitations of the study and how limited the application is to real forensic investigations. They then explore some of the media and social media outlets that have clearly misunderstood this paper and seem to have little understanding of forensic science. Finally, Eric and Glenn look at some quotes and comments from knowledgeable sources who also have recognized the flaws in the paper, the authors’ exaggerations, and lack of understanding of the value of their findings.Gabe Guo et al. ,Unveiling intra-person fingerprint similarity via deep contrastive learning.Sci. Adv.10, eadi0329(2024). DOI:10.1126/sciadv.adi0329https://www.science.org/doi/10.1126/sciadv.adi0329https://www.engineering.columbia.edu/news/ai-discovers-not-every-fingerprint-uniquehttps://for-sci-law.blogspot.com/https://www.cnn.com/2024/01/12/world/fingerprints-ai-based-study-scn/index.html
In this episode, Eric and Glenn interview Caitlin Rough, a Masters student at the University of Western Sydney. Glenn saw Caitlin present at the IAFS conference back in November 2023. She comes onto the podcast to discuss her research project involving the interactions of latent prints (sebaceous residues) and blood. This work is near and dear to Glenn because of his previous work with Praska (see reference below). Caitlin discusses her observations with blood and a new twist of applying blood through various blood stain pattern mechanisms, such as swipes, spatter, pooling, and dripping. She observed the blood’s lipophobic reaction to the sebaceous ridge detail, which re-distributes the blood (often into the furrows of the mark). She also observed intermittent reactions of the blood with unknown components in the residue (as Glenn and Praska previously did). The guys discuss the implications of the research and next steps with Caitlin.Praska, N. and G. Langenburg. “Reactions of latent prints to exposed blood.” Forensic Science. International. 2013. (224): 51-58. 77Bloody fingermark training available at www.EvolveForensics.comhttps://learn.evolveforensics.com/product-category/webinars/
Eric and Glenn discuss their holiday parties and preparations, play another round of "Where in the Whorld?", and then interview a guest all the way from Sydney, Australia. Teneil Hannah, a PhD candidate at the University of Technology Sydney (UTS), joins the podcast to talk about some of her recently presented research on fingermark grading/quality scales. These are scales used by practitioners or researchers to evaluate the effectiveness of potentially new processing and visualization techniques to develop latent fingerprints. Whenever a laboratory is deciding to adopt a new treatment or change an existing one, the lab is expected to perform testing to evaluate the technique. There are a number of scales available to assess latent prints. Teneil walks us through what the most common scales are, who is using what, why are these scales important, and what modifications can be made to existing scales to improve their wide spread adoption and usage.References from Episode:CAST ScaleBandey, H.L. and Gibson, A.P., The Powders Process, Study 2: Evaluation of Fingerprint Powders on Smooth Surfaces, in Fingerprint Development and Imaging Newsletter. 2006.UNIL ScaleBecue, A., Moret, S., Champod, C., and Margot, P., Use of quantum dots in aqueous solution to detect blood fingermarks on non-porous surfaces. Forensic Science International, 2009. 191: p. 36-41.UC ScaleMcLaren, C., Lennard, C., and Stoilovic, M., Methylamine Pretreatment of Dry Latent Fingermarks on Polyethylene for Enhanced Detection by Cyanoacrylate Fuming. Journal of Forensic Identification, 2010. 60: p. 199-222.IFRG GuidelinesInternational Fingerprint Research Group, Guidelines for the assessment of fingermark detection techniques. Journal of Forensic Identification, 2014. 64: p. 174-197.Hockey, D; Dove, A; Kent, T. Guideline for the use and statistical analysis of the Home Office fingermark grading scheme for comparing fingermark development techniques. For Sci Intl 318 (2021) 110604.Hanna, T; Chadwick, S; Moret, S. Fingermark quality assessment, a transversal study of subjective quality scales. For Sci Intl 350 (2023) 111783.
Glenn Langenburg and Eric Ray spent the past few months traveling to conferences far and wide. This episode they catch up with each other on recent travels, stories from the road, and some of the presentations that they saw over the past few months. It's a laid-back episode, so join us for as we catch up with each other. (There's also a big reveal in this episode. Can you figure it out before Eric does?)
Eric and Glenn return with a super-sized episode where they trade courtroom stories. Glenn had two cases in 2023 where the judges and decisions were rather surprising. From being hurried, harried, and harassed, there were some oddball moments for Glenn. Eric similarly shared a few unusual court moments for him. We also encouraged our listeners to share their moments whether you were a witness, attorney or even as a juror, we’d like to hear your stories too!
Eric and Glenn share their adventures at the 2023 International Association for Identification conference held in August in National Harbor, MD in the Washington D.C. area. They discuss various lectures and workshops they attended. They also discuss Becca running the Double Loop Podcast “merch” booth and this year’s hot selling fingerprint tee-shirt. Becca interviews several attendees and gets some of the international flavor that is so much a part of each IAI annual conference.
Eric Ray and Glenn Langenburg are at the 2023 IAI conference in National Harbor, MD with Erin West and Ashley Church of Gap Science. They've developed a series of classes and an entire virtual conference dedicated to training for forensic supervisors and management. How many people should be reporting to one supervisor? What resources are available to forensic professionals? What if you're supervising a discipline that you're not trained in? Listen to the discussion and then join the FREE conference during Forensic Science Week.
To start the episode, Glenn tells Eric a story relating to Edmond Locard and Galdino Ramos, a doctor with an interesting connection to the history of fingerprints. Later in the episode the guys take on a listener question “What forensic discipline is the most reliable?” In order to address the question, they do a quick recap of various studies that attempt to estimate how lay people assess the reliability of different disciplines and contrast those data with black box error rate studies for each discipline, when available. Finally, Eric and Glenn discuss a new paper on DNA from Hicklin, et al. dealing with the accuracy of DNA analysts determining the number of contributors (NOC) to a DNA mixture. This study, and several other DNA papers, tie into the comparison between fingerprints and DNA, and which one they think is more “reliable”. All in all, a good general discussion for lay people and forensic scientists regarding what is meant by “reliable” in the eyes of jurors and what do these studies tell us about the accuracy of these different forensic techniques.
Glenn Langenburg and Eric Ray bring the podcast to the California State Division of the IAI. Tom Busey joins the panel, and they discuss one of Tom's recent papers on an alternate method for calculating a fingerprint likelihood ratio. What if you didn't have to make decisions in fingerprint comparisons anymore? Big thanks again to the CSDIAI for inviting us to hold this panel discussion and for putting on a great conference.
Eric Ray and Glenn Langenburg discuss the recent article from Tom Busey - Tracking the growth of visual evidence in fingerprint comparison tasks. Examiners were shown features one at a time and asked to reach conclusions after each one. The study measured differences from the order of features revealed, their diagnosticity, and their clarity.
Glenn Langenburg and Eric Ray eventually discuss the results of the recent NIST Evaluation of Latent Friction Ridge Technology. But first there are a couple of detours. Glenn discusses recent testimony regarding questionable nanogram testing for the presence of drugs. Eric talks about the Cousins By Blood podcast and his involvement in that case. Once the discussion returns to NIST testing, the guys review the differences between the most recent tests and the previous round in 2012. Follow along with the discussion by viewing the results at: https://pages.nist.gov/elft/elft_1_x/results/
Eric Ray and Glenn Langenburg tackle three new Black Box / Accuracy studies from Austin Hicklin, et al and Noblis. Results from research into the accuracy of forensic handwriting comparison, footwear comparison, and bloodstain pattern comparison have been recently published. The guys break down the nuances of this research and how its similar and different from the latent fingerprint and palm print black box accuracy studies.
Glenn Langenburg and Eric Ray are joined by Alan McNamara to continue discussing the case that sent him to jail. Alan shares his story from the day the police first knocked on his door through the trials and appellate hearings. His first-hand account of this miscarriage of justice is an eye-opener for forensic scientists and for everyone with an interest in the criminal justice system anywhere in the world. Images and reports from this case are available at patreon.com/DoubleLoopPodcast.
Eric Ray and Glenn Langenburg continue their discussion of the Alan McNamara case from the UK. This time they start with the trial and then go through many of the expert witnesses that got involved in this case. Why do all the test lifts from the jewelry box have a wood grain in the background, but there is no grain in the evidence lift? Does the hook or Chinese character shape mean anything? How important is testimony about the homeowner's cleaning schedule? Can latent prints survive regular cleanings? Should there be questions about the accuracy of the latent print identifications to the homeowner? Eric then reads some of the internet comments that were made when the Alan McNamara case was first featured on the BBC's Panorama. Join us again on the next episode where we interview Alan McNamara.
Glenn Langenburg and Eric Ray discuss the case of Alan McNamara from the UK. In this episode we cover the details of the burglary and how the police focused on Alan McNamara. Despite many issues in the latent print evidence, charges moved forward. The prosecution's entire case was based on a single latent print with questionable documentation.
Eric and Glenn return from a hiatus to have a more relaxed catch-up episode. They share an adventure or two including the great Arizona Treasure Hunt that they participated in. Eric shares some experiences from the User Conference he worked. And finally the guys talk about the Double Loop Podcast booth experience at the 2022 Omaha IAI Educational Conference. They play a bunch of clips and recordings from our “Correspondent” Rebecca Coutant who was running the booth and playing “(Wo)Man on the Street” to get some attendee perspectives.
Eric and Glenn interview returning guest, and newly minted PhD, Dr. Henry Swofford on his recent paper, with co-author Prof. Christophe Champod: “Probabilistic reporting and algorithms in forensic science: Stakeholder perspectives within the American criminal justice system” (For Sci Intl Synergy 2020; https://doi.org/10.1016/j.fsisyn.2022.100220). The new article discusses interview responses from judges, prosecutors, defense attorneys, scholars, and forensic laboratory managers regarding their perspective on how to validate, implement, litigate, and communicate probabilistic tools and algorithms in American courts. They discuss different quotes and perspectives from the paper and relate that to their own experiences and observations. Henry also makes an important reference to a companion paper, that provides concrete recommendations and a strategy towards implementation by practitioners: “Implementation of algorithms in pattern and impression evidence: A responsible and practical roadmap” (FSI Synergy 2021; https://doi.org/10.1016/j.fsisyn.2021.100142).
Glenn Langenburg and Eric Ray sit down with Brianne Breedlove from Uncover Forensics to discuss online training and how things have changed in professional forensic training over the past few years. What are the challenges in this new format? What are the benefits that we could never do before? At the beginning Eric and Glenn finish off last episode's discussion on disclosure. Make sure to check out the new shirts and other merchandise at DoubleLoopPodcast.com.
Today, Eric and Glenn FINALLY review the Stephan Cowans case, a case of an erroneous identification from Boston where a fingerprint identification was critical evidence used to convict Cowans in 1998. This case is one of the few Innocence Project cases where there was an erroneous fingerprint identification but DNA was able to exonerate Cowans in 2004 (and the true source of the latent print was later identified). Eric and Glenn go through the major elements of the case and the subsequent review of the Boston Police Department Latent Print Unit by an external consultant. At the end, they discuss the critical improvements and advancements made in the wake of the error and why these cases are still important today to review and remember.
Eric Ray and Glenn Langenburg go round and around on the topic of how to disclose errors to defense. Should your errors be listed in your CV? Should they be disclosed to defense automatically? Only on request? They guys finish the episode reading an email from a listener about their experience with QC after an erroneous identification.
In this episode, the guys interview fingerprint examiner, multi-book author, and instructor, Hillary Moses Daluz . Hillary discusses her new book "Courtroom Testimony for the Fingerprint Examiner" (CRC Press; 2021). They discuss some of the difficult hot topics that examiners struggle with during testimony and how keep testimony training positive and optimistic.
Eric Ray and Glenn Langenburg catch up on a mix bag of topics in the first episode of 2022. Emails on the new conclusion proposal, setups for photography with transmitted light, and the main topic on "qualitative statements". ANAB accreditation requires agencies to include a statistic or a qualitative statement when reporting an association. What does that mean? What qualifies as quantitative? Is this a new thing? Thanks for listening for another year!
In this episode, the guys talk about Thanksgiving: Eric’s amazing food preparation and Glenn’s travel to Canada to teach. Eric also gives a plug for Kasey Wertheim’s fingerprint book library that is up for auction. In the main segment, they discuss two of the new ASB proposed standards out for public comment. Specifically, they examine differences with these documents and those proposed by OSAC, noting the pros and cons between the two versions. They discuss the ASB 013 – “Standard for Friction Ridge Examination Conclusions” and ASB 144 – Best Practice Recommendations for the Verification Component of Friction Ridge Examination. Merry Christmas and Happy New Year!
Eric Ray and Glenn Langenburg discuss the recent paper on Blind Proficiency Testing from the Houston Forensic Science Center: "Latent print quality in blind proficiency testing: Using quality metrics to examine laboratory performance" by Brett O. Gardner, Maddisen Neuman, and Sharon Kelley. The paper describes the results of over two years of blind proficiency testing in the latent print unit. No false positive errors were detected over all samples when the examiners were not aware that they were being tested. The paper also describes the use of LQMetric in measuring the Quality of the sample latent prints. A fantastic paper and a great model for other agencies to imitate.
The long awaited/dreaded return of the “Dad Joke Intro”! In this episode, Todd Weller (firearms expert) returns to the show to talk to Eric and Glenn about the article on inconclusive decisions by Itiel Dror and Nicholas Scurich [(Mis)use of scientific measurements in forensic science; Forensic Science International, 2020; 2:333-338]. Todd gives his views on how the article mischaracterizes the error rate computations and designs of various firearms studies. The guys try to relate it back to their view on the article and fingerprint studies.
Return with Glenn and Eric to the IAI Conference in Nashville, TN. The guys are joined by Josh Connelly, Kurt Aebersold, JP Rodriguez, and Claudine Carter Pereira. New accuracy studies, open field research, and stat talk. And we're already looking forward to next year's conference in Nebraska!
Glenn Langenburg and Eric Ray review the 2020 article from Itiel Dror and Nicholas Scurich. "(Mis)use of scientific measurements in forensic science" was published in Forensic Science International: Synergy. The article criticizes published accuracy studies in the latent print and firearms disciplines and suggests an alternative method for handling inconclusive decisions and calculating an error rate for the field. The episode details factual errors in almost every part of the article and suggests the real motivation behind these arguments. But first Eric and Glenn read some emails and catch up on our return to conferences.
Glenn Langenburg and Eric Ray discuss how to testify in court after an error occurs. Examiners nervous about upcoming testimony can find tips whether you made the error or a co-worker made an error and whether it was an erroneous identification or an erroneous exclusion. The court and juries do not expect us to be perfect, and we should claim to be. It's important to be able to discuss the Quality Assurance protocols that our labs have in place. Watch Eric and Glenn compare fingerprints here - https://youtu.be/C5KmM6cAKpk And join us for Wed Happy Hour here - https://discord.gg/b39pp6j
In this episode, the guys return for Round 2 with Dr. Heidi Eldridge and Prof. Christophe Champod. This time, they discuss the second paper arising from the palm print black box study (discussed in DLP Episode #234). The focus in this episode is “Mind-set – How bias leads to errors in friction ridge comparisons” by Eldridge, de Donno, and Champod in Forensic Science Int’l 318 (2021). This paper explores how instances of false positives and false negatives may have resulted from cognitive biases and assumptions formed about the latent print during the examination. The authors discuss some of the differences between mindset in false positives versus false negatives. They end the interview with suggestions for breaking mindset and reducing errors.
Link to paper: http://dx.doi.org/10.1016/j.forsciint.2020.110545
Glenn Langenburg and Eric Ray are joined by Todd Weller to discuss the firearms/toolmarks discipline. Todd was involved in the NY firearms case from Episode 227 and shares his experiences there. The guys then talk through accuracy studies for firearms examiners and similarities and differences between firearms and fingerprints. Lots to cover in an extra-long episode.
In this episode, Eric and Glenn are joined by Dr. Heidi Eldridge and Prof, Christophe Champod, the authors of "Testing the accuracy and reliability of palmar friction ridge comparisons - A black box study". The guests describe the design, the aims, and the results of the study. We get into discussions about the meaning and usefulness of error rate statistics and confidence intervals from performance studies such as this.
Link to the Article (open source): http://dx.doi.org/10.1016/j.forsciint.2020.110457
Link to study results in shinyapp: https://cchampod.shinyapps.io/Results_BBStudy/
Link to confidence interval tools in shinyapp: https://cchampod.shinyapps.io/app_CI/
Link to error rate primer prepared by Champod, Eldridge, Lambert: zenodo.org/record/3734560#.YB8Ki5NKhbt
Glenn Langenburg and Eric Ray finally get back on track with a review of a recent article on GYRO markings. "Evaluating the Accuracy and Weight of Confidence in Examiner Minutiae Annotations" was written by Jeremy John and Henry Swofford and published in the JFI. The study measured whether examiners placed minutiae markers on true minutiae using Green, Yellow, and Red markers. It then compared the color choices of examiners against the color choices of the automatic LQMetric and DFIQI algorithms. Eric and Glenn will soon be publishing videos of themselves conducting comparisons, using GYRO, and discussing their similarities and differences. Keep an eye out for those coming soon. Also, the 8pm (ET) Wednesday night virtual Happy Hour continues at https://discord.gg/b39pp6j
Glenn Langenburg and Eric Ray review the newest article from Austin Hicklin, Bradford Ulery, Madeline Ausdemore, and JoAnn Buscaglia. Why do latent fingerprint examiners differ in their conclusions? reviews data from the Black Box, White Box, and Eye Tracking papers, summarizes trends through all of that research, and recommends changes for the fingerprint field.
After some Halloween talk, Eric and Glenn discuss this episode’s research article: “The Utility of Expanded Conclusion Scales During Latent Print Examinations” by Carter, Vogelsand, Vanderkolk, and Busey in J Forensic Sciences (online, 2020). This study examines the results of 27 experts who completed 30 comparisons under a 3-point SWGAST scale versus 30 comparisons under a 5-point OSAC scale. The guys discuss error rates, changes in apparent decision thresholds, and the rate of misleading evidence of “support for…” decisions.
Article: https://onlinelibrary.wiley.com/doi/abs/10.1111/1556-4029.14298?af=R
Interpol Paper Reference: https://www.sciencedirect.com/science/article/pii/S2589871X20300139
In this Halloween episode, Eric and Glenn discuss a new paper published by Koehler and Liu titled “Fingerprint error rate on close non-matches” (Journal of Forensic Sciences, Sept. 2020). The paper raises a lot of discussion between the guys regarding close non-matches, inconclusives, training, and testimony. They each have a different take on some of the key issues in the paper, but in the end identify what common ground on which they agree.
Glenn Langenburg and Eric Ray pay special tribute this week to a giant in the fingerprint world, Bob Garrett. With the passing of Bob and a few other close friends and colleagues, Glenn and Eric want to look back at the contributions of Bob Garrett in particular. In his single year as president of the IAI, he was instrumental in responding to the NAS Report, addressing the McKie controversy, and moving forward the Standardization II Committee. Please join us in remembering Bob and all of the other friends and colleagues that we've recently lost.
In this episode, Glenn and Eric discuss a recent case Glenn was involved in: a knuckle-crease case. The case had a Daubert hearing in addition to trial testimony for jurors. The guys discuss if non-friction ridge skin associations would meet the Daubert factors. If you were preparing for such a hearing, what research and testing would you need to demonstrate expertise of the expert, or demonstrate reliability of the methods and principles? Does expertise in fingerprints using ACE-V translate to the comparison of non-friction ridge skin or any other objects you might encounter in photographs? Stay tuned…their answers may surprise you!
Glenn Langenburg and Eric Ray review a recent court decision on firearms testimony. NY v Ross was a recent Frye case where the testimony of firearms examiners was restricted to only class characteristics. Was this a fair decision? Did the judge raise good points? How does this case relate to latent print testimony and latent print accuracy studies? Join us for an hour of fun talk as we dive deep into the nerdy intersection of science and law. https://legalaidnyc.org/wp-content/uploads/2020/07/Ross-Frye-Decision_Full-.pdf
Glenn Langenburg and Eric Ray were recently asked which latent print books they recommend the most. This episode they talk through the absolute creme de la creme of fingerprint tomes. New books, old books, green books, blue books. Whether you're developing or comparing ridges, we've got a list of what you need to read. Also make sure to join us Wed nights at 8pm EDT for Virtual Happy Hour at https://discord.gg/b39pp6j
This week, the guys review and share their reactions to the documentary “The Most Dangerous Animal of All” (produced by Campfire Productions and available now on F/X and Hulu). This is a story about Gary Stewart who believes his father, Earl Van Best, Jr. was the infamous Zodiac Killer in San Francisco in the 1960s/1970s. The series reveals who Gary is and his obsession with the Zodiac. Then it shows all of the extensive evidence that he and his co-author accumulate to prove Earl Van Best was the Zodiac. Glenn and Eric discuss the forensic evidence in this case and share their views and reactions. At approximately 53:00 minutes we give a spoiler alert as the series and this podcast episode take a turn. We highly recommend watching the 4-part documentary first before hearing our views on this case.
Discord link (Wed 5-7PM PST) https://discord.gg/b39pp6j Webinars: www.evolveforensics.com
Glenn Langenburg and Eric Ray take a break from normal interviews and research reviews to host a laid-back happy hour discussion on how things have been different in the past few months in forensic crime labs. Carey Hall, Becca Coutant, and Josh Connelly join our discussion that meanders from discussions on web-based training, remote testimony, recent changes to in lab life, and TV recommendations. Our Discord server is at https://discord.gg/b39pp6j. Happy Hour is Wed's at 8pm EDT.
Eric and Glenn wrap up their “activity level series” by discussing two articles (Girod, et al. 2016; and Hinners, et al. 2020) which propose determination of aging of latent fingerprint residue. The techniques use instrumental techniques to identify breakdown products of various fatty components in latent print residue, and use these results to classify whether a latent print is a couple of days old, or older (up to a week or month old depending on the paper). This is a nice finale to the series to explore what the realities and limitations of aging latent prints entails, rather than relying on visual inspection and qualified “consistent with” statements that previous episodes revealed could be misleading or just plain wrong. Glenn also starts the show by relaying a little bit of his experience joining the new NIST/NIJ Human Factors Expert Working Group on DNA mixture interpretation.
In the final and third part of the series on the Massachusetts drug scandals and Netflix documentary, we interview Luke Ryan, the defense attorney featured in the documentary and who represented several of the clients affected by the scandal. Luke described how and why he fought to uncover the truth that was being swept under the rug by the Attorney General’s office. We also discussed a number of other issues that were not shown in the documentary, including deliberate and willful collusion by the drug chemists to mislead the court, the results of a quality audit that occurred, and early signs that drug chemists were engaged in misconduct for years. Luke also shared his views on a number of criminal justice and social issues such as civil forfeitures, the war on drugs, discovery of predicate questions, and field test kits for narcotics. Settle in for a super-sized episode uncovering the unbelievable and fantastic story behind the Netflix documentary and the perfect storm that could allow such behavior to go unchecked for years.
Eric and Glenn finish out their discussion of the new Netflix documentary “How to Fix a Drug Scandal” (2020). In this episode we switch our focus on the dry-labbing of drug tests by Annie Dookhan, and how long it took for those tests and convictions from those test to finally get tossed. The episode concludes with the story of Luke Ryan and his crusade to finally find the evidence that clearly demonstrated that Sonja Farak had been using drugs for years and not just months.
Join Glenn and Eric on Discord for virtual Latent Print Examiner Happy Hour, Wednesdays 8-10PM EST (5-7PM PST) during the Shelter in Place orders (discord.gg.b39pp6j).
In the wake of COVID-19 and so many of us staying at home, we decided as an April Fools’ Episode to make a list of movies that we enjoy and feature an aspect of forensic science. Eric and Glenn run down our top 10 movies (with two “so bad, they’re good” recommendations) and a few honorable mentions for you to consider while deciding what movies or shows to binge. We also alert listeners at the end to a call for research, regarding a new “verification practices” survey that you can take.
In the first of two episodes, Glenn and Eric discuss Netflix’s “How to Fix a Drug Scandal” (2020), covering the actions and consequences of two Massachusetts drug chemists. In this episode, they mostly focus on the Sonja Farak aspect, who was a drug chemist, addicted to drugs and stealing drugs from her standards cabinet and evidence. The guys discuss the issue of ‘random drug screenings’ of crime lab employees and the lack of other various controls in the U.S. The lack of controls can allow circumstances like this to occur, here and elsewhere, undetected for a long time. They also share some personal experiences from their past related to friends/co-workers with serious drug problems. Also, they remind everyone to join them on Discord for virtual Latent Print Examiner Happy Hour, Wednesdays 8-10PM EST (5-7PM PST) during the Shelter in Place orders (http://discord.gg.b39pp6j).
In this episode, Eric and Glenn start the show discussing a few kind emails and reviews of this podcast. They also talk about a weekly social event online—an online Happy Hour on Discord for Latent Print Examiners and friends of the show. In the main segment, the guys review Hundl et al. (2019) “Implementation of a Blind Quality Control Program in a Forensic Laboratory” in the Journal of Forensic Sciences. This research paper discusses the results of introducing over 140 realistic ground truth cases, without the analysts’ awareness that the case is a test case, at the Houston Forensic Science Center (HFSC) in Houston, Texas, over a period of several years.
Join other listeners of the Double Loop Podcast for a LPE Happy Hour on Discord, Wednesdays 5-7pm PDT (8-10pm EDT) at https://discord.gg/b39pp6j
The case against David Camm is about to be turned on its head. Eric Ray and Glenn Langenburg continue the story with a second and third trial and the introduction of a mountain of evidence against a new suspect. The episode concludes with an in-depth discussion on the importance of considering multiple scenarios in bloodstain pattern and all forensic disciplines. It all ties back to our previous discussions of activity level propositions.
In this multi-part series on the Indiana v. David Camm case, Eric and Glenn review the evidence over multiple episodes. In this first episode they review the evidence of the Prosecution and the first trial. There is discussion regarding latent print evidence, DNA evidence, crime scene reconstruction, medical examiner findings, and blood stain pattern evidence. The blood stain evidence is fairly critical in placing David Camm at the scene of a triple homicide (his wife and two young children).
Glenn Langenburg returns from international travels (just in time) and brings stories from distant lands of England and Minnesota. As the discussion turns to conclusions, Eric Ray brings an update from the OSAC Friction Ridge Subcommittee. Check the NIST OSAC website in the near future for updated versions of Friction Ridge Subcommittee proposed standards.
Glenn Langenburg is joined by Simon Bunter from Keith Borer Consultants to discuss a number of cases where activity level propositions were key factors. Can a print survive after the surface is cleaned? What if the surface is painted over? Simon tells some amazing stories that should make every latent print examiner question the timeline of when a latent print was left on a surface.
Eric Ray and Glenn Langenburg are joined by Anouk de Ronde from the Amsterdam University of Applied Sciences to continue the discussion on activity level propositions. Anouk has published on how to construct a logical framework for considering all the information in a latent print to assist in establishing probabilities for competing hypotheses. Did he climb the railing or just lean against it? Was the pillowcase changed or was the pillow pressed down? Just like you wouldn't reach an Identification without looking at each individual minutiae, this framework allows for examination of each data point before making a conclusion on the likelihood of different activity level propositions.
In this episode Glenn and Eric dig into ‘activity level propositions’, which will start a series of episodes that takes a deep dive into this topic. We lay the groundwork for the topic by discussing fundamental forensic science papers, such as Evett, et al. “The impact of the principles of evidence interpretation on the structure and content of statements” (Science & Justice, 2000) and other works by Cook and Jackson. We highlight the need for formal declaration of propositions regarding ‘source’, ‘activity’, and ‘crime (offense)’ levels. Lastly, we discuss aging (time since deposition) of latent prints and the dangers of these statements based on a visual exam alone. We reference Girod, Ramotowski, et al. “Fingermark age determinations: Legal considerations, review of the literature, and practical propositions” (For Sci Intl, 2016) for important points here. Also Glenn has some news at the beginning of the show to share with Eric regarding DNA.
Eric Ray and Glenn Langenburg get passionate about policies. Stirred up about standards. PO'd about SDO's. After a quick refresher on how NIST, OSAC, AAFS, and ASB fit together in the Standards Development process, Eric and Glenn give an update on the draft standards for latent prints. Where are the standards that we've been waiting for? There was a recent meeting the Friction Ridge group with ASB, and things did not go well for those of us that would like to see the process move forward. While you're waiting for things to move forward, don't forget to check out the Double Loop Podcast merch store at www.doublelooppodcast.com
In this episode, Glenn and Eric interview Brendan Max, Chief of the Cook County Public Defender Forensic Science Unit in Illinois. They discuss his new article “Assessing Latent Print Proficiency Tests: Lofty Aims, Straightforward Samples, and the Implications of Non-Expert Performance” (Max, Cavise, and Gutierrez in JFI 2019;69(3)). Brendan shares his views on proficiency tests: are they meaningful? What about verifications in proficiency testing? What does it mean to ‘fail’ a test? How do lawyers and judges view proficiency tests? He describes his basic strategy for litigating forensic evidence and explains why the research in the field of latent prints is so critical. Pay attention towards the end: Eric legitimately stumps Glenn with a great question!
Eric Ray and Glenn Langenburg talk through the latest document out of the OSAC Friction Ridge Subcommttee. Last month they released an updated, and detailed, process map for friction ridge examinations. Follow along by downloading the pdf from the OSAC FRS website, https://www.nist.gov/topics/forensic-science/friction-ridge-subcommittee.
Eric and Glenn are also happy to announce the Double Loop Podcast merch store. Go to doublelooppodcast.com, click on the Store tab, and help support the show.
This episode, the guys review and discuss a paper about resolving conflict resolution from Montani, et al. titled “Resolving differing expert opinions” (Science & Justice 2019). They explore the nuances of the recommendations from the paper and Glenn applied the principles to a recent case and conflict resolution he experienced. But before getting into the paper, Eric gushes some more about his new job and discusses a recent podcast that he guested on (“Stinker Madness”). Glenn also discusses some draft documents available through OSAC and some upcoming changes to OSAC.
Eric Ray starts the show sharing some big news with Glenn Langenburg and the listeners. The guys are then joined by AC Brogdon, president of the California State Division of the IAI for an discussion on the importance of the work that we do. AC shares some stories of his early life, and how those experiences shaped the person that he is and how that continues to inspire and motivate him. It's vitally important for examiners and investigators to remember the victims as they do their work and that it's not just another day at the office for those directly affected by the crime. Part of maintaining that motivation is to recognize that this job comes with unique stress, especially for those collecting and documenting evidence at the crmie scene. Employee assistance programs are available through most agencies to help all of us deal with the terrible things that we can exposed to every day.
In this episode, Eric and Glenn tackle the 2018 proposed OSAC Friction Ridge Subcommittee (FRS) Standards for Conclusions. They review the entire document and provide the definitions for 5 conclusions: identification, exclusion, inconclusive, and support for same/different sources. They give their thoughts and reactions to these terms and give examples of when they might apply. Glenn discusses an upcoming jury trial where he will be using these terms and how they appear in his reports. Bonus: an unexpected discussion of Downton Abbey! Upcoming classes mentioned at the end. Note: this episode has premium content for our Patreon Supporters.
Glenn Langenburg leads a panel discussion (with Eric Ray joining via phone) at the Pacific Northwest Division of the IAI / Northwest Association of Forensic Scientists Joint Conference with guests and Janis Puracal from the Forensic Justice Project and Carey Hall. The panel discussion explores the Janis's history with exonerations, innocence, justice reform, and forensic science and the challenges that face those that have been erroneously convicted. The conversation also explores the challenges that forensic scientists face in these areas and steps that they can take to ensure neutrality and that justice is served.
Head to DoubleLoopPodcast.com for more episodes and look through the soon-to-arrive Merch store!
Join Glenn Langenburg and Eric Ray in Reno, NV for the 2019 International Association for Identification conference. We are joined by Becca Coutant, Carey Hall, Nicole Praska, Claudine Carter Pereira, and Jason Jardine and cover a number of topics including limited examinations, defense attorney perspectives, conclusion terminology, blood prints, management, and stats. There's even a little story of Glenn losing his cool and an out-take for the blooper reel. The conference was fantastic, and big thanks to all of the new listeners that we met during the week.
To celebrate 200+ episodes, an old photo of Glenn with John Vanderkolk is included.
Eric Ray and Glenn Langenburg review a new paper that's been long in the making. "The permanence of friction ridge skin and persistence of friction ridge skin and impressions: A comprehensive review and new results" by Monson, et al. was recently published in Forensic Science International. The paper details the persistence and permanence of 1st, 2nd, and 3rd level detail over multiple years. There are important takeaways from the paper although it isn't quite the level of the FBI/Noblis papers. So let's see what the guys think.
Eric Ray was recently teaching in Idaho (the ID state) and had the opportunity to sit down with Nick Craven, Katlyn Shelar, Whitney Betzel, and Tara Koho and talk with them about topics ranging from latent print exclusions, AFIS candidate lists, and the future of statistical models. Glenn Langenburg then joins Eric to continue the discussion with some follow-up points and continuing the conversation further into Exclusion policies and requirements, the nature of risk, and a preview on how to use a 5 Conclusion scale.
Eric Ray and Glenn Langenburg discuss the new article from Austin Hicklin, Brad Ulery, Tom Busey, and company researching latent print examiners with eye tracking equipment. Gaze behavior and cognitive states during fingerprint target group localization was published in Cognitive Research and examines what we look at and how context plays a huge part in this process. Download the paper online and follow along as we explore a great new paper.
EPISODE 200!!! - Eric Ray and Glenn Langenburg celebrate the big number 200 with an overseas interview with Australian latent print examiner and friend of the show, Michael Whyte. The guys talk forensics down under, some of the travels, teaching, and technology that Michael is involved with and announce DoubleLoopPodcast.com. Check it out, and let us know how we can make it even better.
Eric and Glenn return from a couple weeks off of crazy travels with a few stories from the road including a "Men Who Love My Little Pony" ("Bronies") cosplay conference. In this episode, the guys sit down for a fantastic interview with Duke Law Professor Brandon Garrett to discuss his and colleagues' recent juror study. The most recent paper provides fingerprint proficiency test results to mock jurors to see how this information may impact their decision making and how reliable they believe fingerprint evidence to be.
Eric Ray and Glenn Langenburg start the show talking about some exciting new classes that they have developed. Then they discuss which is more correct: 2009 "NRC" Report or "NAS" Report. Finally, they describe the available facts in the recent Archie Williams Innocence Project exoneration case. He was freed after 36 years in prison for rape based on eyewitness identifications, but an AFIS hit now implicates another person.
Glenn and Eric start with a brief chat about ethics and the recent JFI letter regarding testing and studies involving human subjects. They then jump into the main discussion on the "Review of Several False Positive Error Rate Estimates for Latent Fingerprint Examination Proposed Based on the 2014 Maimi-Dade Police Department Study" by Madeline Ausdemore, Jessie Hendricks, and Cedric Neumann. The review found that the data best fit a model of two error rates: one for when the true match is not present and one where the true match is one of the individuals presented. The article concludes with follow-up letters to the JFI from Igor Pacheco, Brian Cerchiai, Stephanie Stoiloff, Glenn Langenburg, Jonathan Koehler, Carey Hall, and Brendan Max. This episode is sponsored by GO EVIDENCE.
Eric Ray and Glenn Langenburg discuss post-Laura Interview thoughts after last episode's "lay person" interview. They tie in a new paper surveying mock-jurors, published by Gianni Ribeiro from Australia. Later, Gianni calls in from Oz to discuss her research. Oh, and Eric and Glenn both come up with genius ideas this episode.
Glenn Langenburg and Eric Ray interview friend-of-the-show, Laura Keck, and dive deep into how forensic evidence is interpreted by a lay person. Does one fingerprint identification vs. 13 fingerprint identifications make a difference? What if the prints were on an inner drug baggie vs. an outer drug baggie? What is an acceptable error rate for latent prints or DNA? What if there is no other forensic evidence? Laura's perspective as a lay person (but with knowledge and interest in forensic science) and what she expects from expert testimony should lead to experts taking a close look at how they testify, what they examine, and how to prepare for court.
Eric Ray shares some big news and then shares a story about the dictionary. Glenn Langenburg brings another Super Fan into the fold as the Double Loop Podcast website starts to come together and some new research from Australia ( https://www.youtube.com/watch?v=7dG6Rw8_KLg ). They both then revisit the discussion on investigative leads. It's important to understand the distinction between reporting AFIS hits as preliminary without verification and a true "investigative lead" where there are only limited features in agreement. This episdoe is sponsored by Go Evidence Laboratories.
After arguing about the Mandela Effect, Glenn and Eric catch up on some email and discuss ANAB AR3125 7.8.1.2.2 and how this impacts reporting conclusions. Glenn talks about using verbal LRs to express the perceived weight of evidence. Then the guys review a paper from Israel on investigative leads (Attias, et al. 2015) from J of For Sci & Criminology.
Glenn Langenburg and Eric Ray are proud to be joined by Mark Stolorow. Before his years guiding the creation of the OSAC and his days with NIST, he had a varied history getting kicked out of the chemistry department, avoiding the draft, working as a cop, researching blood typing, and wearing plaid jackets. Listen to the interview for all the details of a fantastic career. This episode is sponsored by GO EVIDENCE LABORATORIES.
Eric Ray and Glenn Langenburg are joined for another episode discussing statistics and probabilities by Professor Christophe Champod from the University of Lausanne. Christophe takes us on a history of his work on fingerprint statistics, his past, current, and future research projects, his hope for the future of statistics in fingerprint comparisons, and how the newest Swiss model is available for use through the Pianos software. This episode is sponsored by GO EVIDENCE.
Eric Ray and Glenn Langenburg interview Australian researcher Gianni Ribeiro at the December 2018 OSAC meeting in Phoenix, AZ. Gianni tells the guys about her research interests studying how juries weigh evidence vs. alibis and other jury studies. She also talks about her impressions of the experts gathered at the OSAC meeting, the discussions going on related to likelihood ratios, and the battles over issues big and small in various subcommittees. This episode is sponsored by GO EVIDENCE LABORATORIES and is sponsored by IDEMIA.
Glenn Langenburg and Eric Ray are joined in-person by Henry Swofford as they discuss his career with the Army Crime Lab and the development of FRStat, a model that produces a similarity score between two compared fingerprints and a ratio of how that score fits into same source or different source distributions. The guys discuss why the model was developed, how it's being used, and some of the models limitations. This episode is sponsed by GoEvidence Forensic Laboratories, and this episode is also sponsored by IDEMIA.
Glenn Langenburg and Eric Ray are joined by Cedric Neumann to discuss all things statistical models, probabilities, likelihood ratios, Bayes factors, and more. Cedric discusses his history of research, his history in forensics, and how that's brought him from Switzerland to the UK to the US. This episode is sponsored by IDEMIA and their new Case AFIS product.
Eric Ray and Glenn Langenburg move into a discussion of a new case with the help of special guest Becki Daher. Richard Ramirez, the Night Stalker, terrorized California in the mid-1980's before he has caught with the help of fingerprints and new AFIS technology. Becki Daher was working for the Orange County Sheriff's Office at the time and lifted the fingerprint from the car window that eventually led to his arrest. Join us in a discussion of Ramirez's crimes, the terror felt by the residents of California, and the high-tech and low-tech techniques that led to his arrest and conviction. (This episode is sponsored by IDEMIA.)
Eric Ray and Glenn Langenburg wrap up the final episode in their series on Making a Murderer Season 2 with all of the craziness that didn't fit in all the previous episodes. Doesn't the bloodstain shape mean that he's innocent? Or mean that he's guilty? What about the lack of fingerprints? The burn barrel? The carpet cleaner? The bullet wax? Is Teresa even dead? Is the Double Loop Podcast just another part of the grand conspiracy by the government against Steven Avery? The answer to almost all of those questions is "no", but listen anyway as we close out this case. (This episode is sponsored by IDEMIA.)
Eric Ray and Glenn Langenburg start to wrap up this second season of Making a Murderer with a discussion of the other new suspects in the case, a bit of internet drama, and the vast Wisconsin conspiracy. They then finally move into the discussion of Brendan Dassey and his ongoing appeals process, and how difficult it is for federal courts to review state court decisions. (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray spend this episode talking about even more of the forensic evidence from the second season of Making a Murderer. They start with a review of the DNA evidence from the hood latch and the bullet fragment. Can there be too much DNA? They also discuss the trace analysis of the bullet fragment, the lack of fingerprints, the mysteries of brain fingerprinting, and even more of the evidence in the Steven Avery case. (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray delve into the second season of Making a Murderer. They start by reviewing the evidence that they had discussed from the first season and then discuss their impressions of the new characters in the docu-series. They then move into a detailed discussion of the experiments conducted by Kathleen Zellner and her new forensic experts on behalf of Steven Avery. The blood and bloodstain patterns are covered. (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray are joined by John Swartz, retired from the Tucson Police Department, for a discussion on the Prime Time Rapist case from the mid-1980's. John talks about how the series of 30 attacks on 90 people affected the Tucson community and the department investigating the crimes. Before the perpetrator could be caught, there was a fingerprint examination error that led to other mistakes and civil rights violations. After discussing the details of the case, Glenn and Eric ask John about how the error affected the examiner, the latent print unit, and how the unit was treated by other agencies after the error.
Eric Ray and Glenn Langenburg begin the episode with a discussion of an article from a law journal by Barbara Spellman titled, Communicating Forensic Evidence: Lessons from Psychological Science. Among her main points are that statistics, likelihood rations, and random match probabilities are terrible ways of communicating information to juries. She goes on to say that there are a number of misconceptions in latent fingerprint comparisons that must be addressed to juries and that analogies might be a better way to convey information to them. While Glenn and Eric agree and disagree with some of those points, they conclude the episode by reviewing a number of their favorite analogies that they use when testifying or teaching. (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray report on a heated and controversial topic that caught the attention of the latent print world in the summer of 2018, the re-designed IAI Re-Certification test. Every five years, Certified Latent Print Examiners must take a comparison test. The old one was notoriously easy, but that has recently changed, and the error rate was higher than some expected. Carl Speckels raised the topic on the CLPEX.com message board and it was discussed at length at the 2018 IAI Conference. The topic is discussed even further here with some suggestions on how to improve the test while keeping it an important aspect of latent print examination. (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray interview Teresa Wu from IDEMIA about the new product launch of IDEMIA's Case AFIS. The new system can quickly scan in exemplar prints from any type of standard or non-standard cards which then serve as a mini-database for an AFIS search. Efficiency is vastly improved when the computer takes care of the searching aspect of latent print comparisons. This process can also almost eliminate erroneous exclusions from casework. (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray try to wrap up any final discussion points from The Staircase docu-series. After Michael Peterson's conviction was overturned and a new trial was ordered, new attorneys come in, but an Alford plea is reached and Michael Peterson is released. Should a retrial have gone forward? What decisions did the original judge regret? What mistakes did the prosecution make? What is a blowpoke? And could an owl have been the murderer and/or the murder weapon? (This episode is sponsored by IDEMIA.)
Glenn Langenburg and Eric Ray are graciously joined by Bart Epstein in an interview about bloodstain and other forensic evidence from the trial of Michael Peterson in the death of Kathleen Peterson. Bart Epstein explains his involvement in the case, his opinions on the blood evidence, and where he agreed and disagreed with Duane Deaver and Dr. Henry Lee. This episode is also sponsored by IDEMIA and their new product, Case AFIS.
In our second dive down The Staircase, Eric Ray and Glenn Langenburg start looking closely at all of the forensic evidence available in the case and what it all means. The documentary leaves lots of questions that we try to answer in this episode like: Can you trace an impact back to a point in space? Could the wall, rail, or step have caused all of the impact sites? Where was the defense medical examiner expert? Did the prosecutor have other bloodstain experts ready to testify besides Deaver? Was there castoff? Were there other wounds besides the scalp lacerations? Was it valid to say that there were no other beating deaths without brain or skull injuries? Was there a cleanup? Were the shorts cleaned? Were Deaver's experiments valid? What about his shirt? Quote from the episode, "People need to hear this evidence. Because I think when you watch these documentaries, you're back and forth. And if you're really suspicious of law enforcement, then you come out of this going, 'This guy got railroaded.' This guy was innocently convicted. This is a BS case. It was all on lies. But I want to go back to the evidence. I haven't seen it in 15 years, but when I saw it then, in 2002, I went, 'Oh. This is open-shut. This is clear-cut. There is no ambiguity here.'" The three big pieces of evidence were that there was an impact site on her head in space which means that someone swung an object to hit her, there was signs of a cleanup and of blood drying meaning that she was not breathing when the 911 call was made, and the blood stains on his shorts means that he was near the body when blood was flying around.
Eric Ray and Glenn Langenburg focus their forensic science backgrounds on the infamous Kathleen Peterson murder as it was portrayed in The Staircase. The guys review their initial impressions of the case and the documentary and then tell the basic outlines of the story where Michael Peterson is suspected, arrested, charged, and convicted of the murder of his wife. There are so many twists and turns to this story that we had to get them all out of the way in this episode before focusing on the forensics in upcoming episodes.
Glenn Langenburg and Eric Ray return to the annual IAI conference in San Antonio to talk to attendees about the interesting lectures and workshops that they've seen this year. Morgan Hays from Florida talks about how he stays current with the field as a supervisor and how the exclusion and verification topics were covered at the conference. Do you trust your verifier? Linda Manigault from Nevada then joins the conversation and discusses the workshops on FRStat and statistical models that she attended. Glenn ends the episode with a BIG announcement!
Glenn Langenburg and Eric Ray wrap up the three-part discussion on the AAAS Report on the Quality and Gap Analysis of Latent Fingerprint Examination. Surprisingly, the guys agree with many of the recommendations and conclusions in the document with an occasional quibble or clarification. As was hinted in the past two episodes, there are more serious concerns with the report's suggested language and proposed limitation of the word "identification".
Glenn Langenburg and Eric Ray continue the discussion on the pros and cons of the AAAS report. Carey participated with the review of the report and discusses the positive recommendations and the limitations that come from the report not being published in a traditional peer-reviewed journal. After that discussion wrapped up, Carey, Eric, and Glenn get a little off-topic and talk about attending AFIS Users' Conferences. Carey and Glenn presented at the most recent Idemia conference on the benefits of the Case AFIS system. Eric talks about a local AFIS conference and user discussions on how data analysis can lead to improved search practices.
Glenn Langenburg and Eric Ray finally get around to discussing the report on latent fingerprint comparisons from the American Association for the Advancement of Science. John Black (from Black and White Forensics) was on the committee that wrote the report and joins the discussion on some of the merits and limitations of the paper. While many of the research recommendations are the next steps that the latent print field needs, they are also the same recommendations made by other reports. One of the report's main failures is the suggested wording for the identification decision.
Glenn Langenburg and Eric Ray are joined by Della Wilkinson from Canada to discuss the final resolution of the Bornyk case from British Columbia. Originally, Judge Funt (see Double Loop Podcast episdoe 10) ruled that the fingerprint evidence would not be admitted after conducting his own study of latent prints and his own comparison. The Crown appealed and a new trial began with the original examiner, the verifier, Della, and Simon Cole. This episode the Double Loop Podcast also pays tribute to Tony Cantu. He will be missed.
Eric Ray sits down for an interview with Simon Cole from the University of California Irvine. Simon explains how he first became interested in forensics and in latent print comparisons in general, and then outlines the history of his criticisms of the field. Glenn Langenburg later joins Eric for a review of the interview and some of Glenn's perspectives on how Simon's criticisms and the latent print response have both evolved over time.
Glenn Langenburg and Eric Ray continue their interview with Matt Marvin from Ron Smith and Associates about the erroneous identifications and eventual exoneration of Beniah Alton Dandridge. This video (available on YouTube via RayForensics.com) goes through an in-depth and technical review of the latent prints, the errors, the exclusions to Dandridge, and the eventual identifications to the victim's son (who discovered the body).
Eric Ray hosts a live Double Loop Podcast discussion at the 2017 Florida Division IAI Conference in Panama City Beach, FL, and Glenn Langenburg joins via phone for the discussion. The audience hit Eric and Glenn with a variety of questions and the conversation swings from AFIS automation to using AFIS as a support for an identification decision. From the requirements that Florida courts put on latent print examiners to how to keep improving yourself so that you can make that jump into a career in forensics.
Eric Ray and Glenn Langenburg are joined by Matt Marvin of Ron Smith and Associates to discuss in greater detail the details of the Beniah Dandridge case. Matt discusses how he and RSA got involved in the case, the history of the Manning murder, the original investigation, the Dandridge trial, his appeals, RSA's involvement, and Dandridge's eventual release. Check back to RayForensics.com soon for a YouTube video detailing the comparisons in this case.
Eric Ray and Glenn Langenburg discuss two forensic cases that have been in the news in the past few years. First, the guys talk about the recent Golden State Killer case. How did DNA testing and genealogy combine to solve these 40 year old crimes? What databases were accessed and was it ethical to do so? Secondly, Eric and Glenn discuss how accessing profiles of Y chromosomes from online sites led Idaho Falls detectives to Michael Usry, Jr. In 1996 Angie Dodge was murdered and Chris Tapp has been in prison for decades, but things get turned upside down when new technology comes into play.
Glenn Langenburg and Eric Ray tackle two articles in one fantastic episode. First, "Lay Understanding of 'Identification': How Jurors Interpret Forensic Identification Testimony" by Henry Swofford and Jessica Cino from the Journal of Forensic Identification. Secondly, the guys tackle a paper from the Journal of Forensic Sciences, "Comparing Categorical and Probabilistic Fingerprint Evidence" by Brandon Garrett, et al. The big question is: should we say "identification" or should we express the same conclusion in a probabilistic manner?
Eric Ray and Glenn Langenburg continue their discussion with Alicia Wilcox on her research into how juries hear forensic testimony. This time we focus even more on questions of opposing experts, error rates, and what's the most important thing for an expert to have. A degree? Years of experience? An accredited lab?
Glenn Langenburg and Eric Ray join with Dr. Alicia Wilcox from Husson University in Bangor, Maine in a discussion of her research juries and their understanding of forensic testimony. Even though forensic scientists may try to present data in precise and sometimes mathematical way, jurors tend to interpret forensic testimony according to whether the evidence fits well into the story that they have constructed of the crime.
Eric Ray and Glenn Langenburg discuss last year's article, Using the PCAST Report to Exclude, Limit, or Minimize Experts by Eric Alexander Vos published in Criminal Justice. We note the extreme bias of the article to exploit the emotions of the judge and jury instead of logic, reason, or data, and we find the serious flaws in many aspects of the paper.
Glenn Langenburg and Eric Ray follow up from last week's discussion of Glenn's recent Daubert hearing with a 2016 article from Jonathan Koehler entitled, Intuitive Error Rate Estimates for the Forensic Sciences. As Glenn suspected, the findings of this article are suspiciously close to the center of the group of choices that participants were presented with. Although there are some larger themes that are interesting, the exact values of the error rate estimates from potential jurors do not match personal experience or even some of the cited prior works.
Glenn Langenburg and Eric Ray return after another hiatus to share travel stories and then to discuss a Daubert hearing that Glenn recently testified in. Short version: having all this new research is way better than when we didn't have it.
Glenn Langenburg and Eric Ray continue their interview with Anja Einseln regarding the merger of ASCLD-LAB and ANAB. Validation of methods and reasons for labs to choose accreditation are some of the many topics covered this time around.
Glenn Langenburg and Eric Ray first revisit a couple of additional aspects of our previous discussion on defense interviews in Illinois before diving into the deep end of accreditation. Anja Einseln joins the Double Loop Podcast as our guest expert on ASCLD/LAB, ANAB, and all things accreditation. In the first half we talk about some of the changes that will be coming with the recent merger of ASCLD/LAB and ANAB and what it means for latent print units in accredited labs.
Eric and Glenn tackle a topic that will be a major concern of labs across the country in the next few years, the merger of ASCLD-LAB and ANAB. Some of the changes include the elimination of Latent Print Appendix, the elimination of the Administrative Review requirement, and slight wording changes that may result in huge changes to latent print reports and notes.
Glenn and Eric continue to discuss the 2017 International Conference on Forensic Inference and Statistics. This time Glenn tells about some troubling trends emerging from Illinois where forensic scientists are refusing to answer questions related to the foundational validity of the discipline. He also touches on new work on a different type of Likelihood Ratio approach from Cedric Neumann and colleageus.
Glenn discusses the recent 2017 International Conference on Forensic Inference and Statistics that was held in Minnesota. Specifically, Glenn helped lead a project that looked at how lay people from different backgrounds interpreted different types of forensic results and how those interpretations were used in a courtroom setting.
Glenn and Eric catch up on how things went at the 2017 IAI Educational Conference in Atlanta, Georgia. Glenn covers a panel discussion on the appropriate use of identification, a new workshop of the PCAST calculations, and discussions about what our error rates should be vs. what juries think our error rates should be.
Eric sits down with Amanda, Harres, Vanessa, Jack, and Judith from the Austin Exclusionology class to talk about latent print topics and to ask questions back at the Double Loop Podcast. Glenn later joins Eric in commenting on how the discussion went and to give his own comments on conclusion language, GYRO, and how juries interpret our results.
Eric and Glenn sit down for an interview with Sandy Siegel and are also joined by a crew of Texas examiners (and one from San Diego). Sandy talks about her start in the field, her time in Austin, and then her new position with the Houston Forensic Science Center. The HFSC is a public/private entity that is separate from the police department and may be a new example for how to structure crime labs in many other jurisdictions.
Glenn Langenburg and Eric Ray follow some good advice from Niki Osborne and interview Dr. Theresa Stotesbury from Trent University in Ontario. Theresa has developed a synthetic blood substitute using sol-gel for use in bloodstain pattern analysis training. We learned a lot and can't wait to find out more.
Glenn Langenburg and Eric Ray read through a new paper from Amy Jeanguenat and Itiel Dror on how workplace stress can affect forensic decision making. The paper makes several great points about how forensic scientists deal with many stresses unique to their careers, including facing outside criticism and working in a culture with zero tolerance for errors.
Eric Ray and Glenn Langenburg delve deep into the data from the White Box and Black Box studies regarding the exclusion decision. Ulery, Hicklin, Roberts, and Buscaglia publish on their exclusion data revealing a strong correlation between exclusion accuracy and the presence of a core or delta in both impressions. Glenn and Eric also look at how minutiae count and latent quality affect exclusion accuracy and then discuss the utility of the exclusion decision itself. Interesting stuff.
Glenn Langenburg and Eric Ray share exciting and groundbreaking news! The FBI latent print unit has officially moved beyond Approach 1. Their examiners may now utilize the inconclusive decision even when better exemplars are not needed. Hopefully, many other Approach 1 agencies start looking to adapt their procedures and move in this same direction.
Glenn Langenburg sits down and interviews Niki Osborne about her work in New Zealand and at the University of California - Irvine in examining how contextual information can influence forensic opinions, especially in the fields of bloodstain pattern analysis and questioned document / handwriting.
Glenn Langenburg and Eric Ray interview Caroline Gibb about her experiences coming up in the latent print field in Australia. LEARN about a woman's obsession with fingerprints from an early age! THRILL to hear about latent print training - Australian style! CRINGE at more bad dad jokes!
Eric Ray and Glenn Langenburg get back into the swing of things with big news in the spring of 2017. The Defense Forensic Science Center (Army Crime Lab) just released a statement saying that their reports would now include a likelihood with each latent print identification. Also, the National Commission on Forensic Science was not renewed by the new Department of Justice.
Eric Ray and Glenn Langenburg review an article in Forensic Magazine that discusses the presentation that Jay Kadane gave at the American Association of Forensic Scientists conference this year. The same arguments are trotted out again, and the podcast sees nothing original nor sophisticated about his argument.
Eric Ray and Glenn Langenburg work their way through the newest position statement from the International Association for Identification. Does it allow examiners to say whatever they want? Is it too vague? Does it overstep the IAI's role, or does it abandon the IAI's traditional role in the discipline? All good questions that Eric and Glenn will try to answer (sort of).
Eric Ray and Glenn Langenburg take an idea from a listener and talk about ideas for science fair projects that feature forensic science! The guys explore ideas in fingerprints but also firearms, handwriting analysis, eyewitness identification, and ink analysis. If you have an interest in forensics and are looking to explore that further in a science fair project, here are some ideas.
Eric and Glenn discuss a few emails before delving into a little more on the PCAST report and its impact on the MO v. Goodwin-Bey case. Firearms evidence linked Goodwin-Bey to a quadruple homicide, but a judge has ruled that the identification decision of the firearms expect will not be heard.
Glenn sits down with Mackenzie de la Hunty at the 2016 Australia New Zealand Forensic Science Society conference in Auckland, New Zealand to discuss her research into Physical Developer. There is definitely a lot to learn about why and how this process works and how agencies can learn how to better utilize this process in the search for latent prints on porous surfaces.
Eric Ray and Glenn Langenburg catch up after an extended hiatus and then review the recent PCAST report. The President's Council of Advisors on Science and Technology issued a scathing report calling for the end of many forensic disciplines. The Double Loop Podcast responds.
Glenn and Eric first cover the new resolution that came out of the IAI 2016 Conference. They then perfectly segue into a conversation on the recent decision to order the release or retrial of Brandon Dassey based on problems with his confession and initial attorney.
Eric Ray hosts the Double Loop Podcast panel discussion at the 2016 IAI Conference in Cincinnati with Glenn Langenburg joining in remotely. Panelists Henry Swofford, Jessica Cino, and Jeniffer Molina discuss latent print conclusions, new wording, court challenges, and other related topics.
Eric is joined by guest co-host Heidi Eldridge in interviewing Hughes Dicaire from Ontario and Christina Amendola and Jenna Alimberti from Massachusetts on interesting lectures and workshops from the 2016 IAI conference in Cincinnati.
Glenn Langenburg and Eric Ray interview Lisa Steele about lawyer stuff, current fingerprint issues, Chicago cases, and just generally get an attorney's perspective on latent prints and forensic evidence.
Glenn Langenburg and Eric Ray finish their discussion of the OJ Simpson trial, the FX OJ dramatization, and the OJ 30 for 30. Mark Fuhrman, Lance Ito, Dennis Fung and all the rest, and how the climate in LA at that time directly led to the verdict.
After the success and interest of Making a Murderer episodes, Glenn and Eric travel back to the 90s to discuss the physical evidence from the murders of Nicole Brown and Ron Goldman and the trial of OJ Simpson.
Glenn Langenburg and Eric Ray discuss the most recent paper from the Noblis team (Bradford Ulery, Austin Hicklin, Maria Roberts, and JoAnn Buscaglia) from the data collected in the White Box study. Interexaminer variation of minutiae markup on latent fingerprints in Forensic Science International looks at how examiners mark points differently when looking at the same image. Clearer points tend to be marked by most examiners but unclear points or ambiguous features in clear areas can have wide variation in markup.
Glenn and Eric listened to the online recordings of the NIST Technical Colloquium Quantifying the Weight of Forensic Evidence. The presentations brought up lots of questions on how forensic scientists should be presenting evidence to juries and the court. Can juries understand complicated models or even nuanced levels of association? Is the search for a mathematical model to express the weight of evidence just a fool's errand?
Glenn and Eric take a look at the newly proposed draft documents from the Department of Justice. These documents seek to provide universal language for testimony and reports for multiple forensic disciplines. The good news is that there is nothing overly shocking or crazy in the latent print language. Examiners should provide comments to the DOJ, but the main content of the documents is in line with language from the past seven years from SWGFAST and the IAI. The link for the draft documents is https://www.justice.gov/dag/proposed-language-regarding-expert-testimony-and-lab-reports-forensic-science
Glenn and Eric received some more emails about the Avery case and fill out yet another episode with the topic. They even manage to debunk a fingerprint myth from the case.
Eric wastes almost an entire episode talking about teaching the Exclusionology class in Taipei, Taiwan and then visits Tokyo on the way back. Glenn adds in a bit about travels to Canada.
Eric (along with Penny Dechant) interviews Melissa, Nicole, and Jackie who all recently attended the Exclusionology class in Ontario, CA.
Glenn and Eric delve into a couple of recent cases involving Chicago PD where defense attorneys have filed motions challenging the admission of latent print evidence.
Glenn and Eric read a couple of emails from non-examiners that came across our Making a Murderer episodes. We ended up spending this whole episode talking about the ideas and comments from those emails.
Unrelated to the episode is the image thumbnail. This is the Christmas gift to our patron in Indianapolis. Turn the image upside-down and it says 'fingerprint'.
Glenn and Eric answer some questions from an email that came in after the Making a Murderer episodes. Is all the extra time used to shield ourselves from bias worth the effort? Do the fact-finders and the general public want our conclusions expressed as associations instead of identifications? Which of our customers decides? The officers, accreditation boards, judges, attorneys, jurors, legislatures?
Eric and Glenn start with a quick review of recent topics from the 2016 OSAC meeting. They then discuss a couple of recent court cases. First, the recent DC Court of Appeals decision in the Marlon Williams case. Second, the motion to preclude latent print testimony in Chicago in the Christopher Robertson case. Both cases focus on how testimony to forensic conclusions may overstate the evidence.
Eric and Glenn continue their discussion of the popular Netflix documentary including further discussions of the physical evidence, the EDTA test, things not discussed in the documentary, and the entire concept of true crime as entertainment.
Glenn and Eric start a two-part podcast discussion on the twisty case of Stephen Avery, now an extremely popular documentary on Netflix. As they wind their way through this very interesting case, the guys try to keep the focus on the physical evidence available and how that all played in to the convictions in this case.
Glenn and Eric discuss a recent article published by Michele Triplett titled, Complexity, Level of Association, and Strength of Fingerprint Conclusions. The guys express their opinions on the strengths and shortcomings of the concepts presented in the paper, why it's a good idea to express the complexity of a comparison, and why this won't solve the problem of errors. Before that discussion Glenn clarifies a few things about ninhydrin bleeding through paper to leave reversed prints.
Glenn and Eric interview Brian Orr with Go Evidence about the vacuum metal deposition technique. Brian and Glenn each share some success stories with VMD and Brian describes how the process works and how it's not as expensive as you might think.
Glenn and Eric first take a long detour to discuss their initial reactions to the newest Star Wars movie (of course), but then talk about a fingerprint identification error involving Melissa Neylon, Inyo County, CA, and Indiana. It's still a little unclear how the fingerprint error took place.
Glenn and Eric throw out a number of topics including how the podcast helps to solve crime and discussions from OSAC meetings.
Eric and Glenn each discuss a paper that they were involved with recently. Eric and the IAI Subcommittee on Probability Modeling published a short article in the ID News summarizing current and future uses of probabilities in fingerprints. Glenn talks about a recent paper on a proteomic approach for identifying blood.
Glenn and Eric talk about a new document released by the Defense Forensic Science Center. That agency has decided to forego using the Identification term when reporting the association of a latent print to a known exemplar. Listen through the episode to hear their new language and Glenn and Eric's thoughts on this new direction.
Glenn and Eric bring up a listener email asking how many candidates examiners should request during AFIS searches. And further, are examiners prepared to compare the increasing number of close non-matches that could arise from better matchers and longer candidate lists. Also, automatically reversing ninhydrin prints.
Eric and Glenn complete their series on the Madrid Bombing Fingerprint Error from the FBI. Even more than 10 years after the error was revealed, there are still very interesting things to learn about this error that led to so many changes and improvements in the latent fingerprint comparison field.
Glenn and Eric continue through the timeline of the Madrid Error or the Brandon Mayfield erroneous fingerprint identification. The guys learn all sorts of new things from the full OIG report that sometimes reveal a new understanding and sometimes contradict the commonly held beliefs of the public and the experts.
Glenn and Eric begin a 3-part review of the full report from the Office of the Inspector General (OIG) on the Madrid Bombing or Brandon Mayfield error from the FBI. This episode starts with a general overview and begins looking at the timeline, including some common misconceptions and inaccuracies that have been taught in fingerprint training classes.
Eric tells Glenn about his recent Arizona Treasure Hunt. The guys then get into a discussion on latent print processing and photography. Do you take photos after each step? After the last step? Only when the latent is better than the previous step? Some other alternative? Solve the puzzle and write in with your own stories about when you process or what crazy requirements your lab has for digital photographs.
Eric starts this episode by doing a short interview with Alice Maceo about her class and some recent adventures. Glenn and Eric then discuss an email asking about setting a point threshold for sufficiency in identifications.
Eric and Glenn talk through the recent news that Beniah Dandridge was wrongly convicted for murder and has served 19 years in an Alabama prison after an erroneous fingerprint identification and other bad witnesses led to his conviction. Major legal issues are coming to light as the courts continued to refuse to re-hear the case even after evidence of Dandridge's guilt was refuted.
Glenn and Eric interview Teresa Wu from 3M/Cogent about the company and new research into preventing errors and statistical models.
This episode sponsored by 3M / Cogent
Eric interviews Glenn about how he got started in latent prints and his favorite time teaching. The guys then discuss regional differences in the latent print field including terms, definitions, and powder color.
Glenn and Eric discuss the McCluskey case out of New Mexico involving testimony on identification to the exclusion of all others, an article on how forensic labs are paid per conviction from the Huffington Post, and Glenn interviews Eric in Part 1 of "Who the Hell are Glenn and Eric?"