Double Loop Podcast

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

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.