Double Loop Podcast

By Glenn Langenburg and Eric Ray

Natural Sciences Science & Medicine Education Government & Organizations Educational Technology

What's Double Loop Podcast about?

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.

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LAST EPISODE

Episode 246 - Stephan Cowan...

05.08.2022

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 ...

Double Loop Podcast episodes:

05.08.2022 Episode 246 - Stephan Cowans Case 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 ...
03.31.2022 Episode 245 - Errors and CVs and Disclosure 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 ...
02.06.2022 Episode 244 - Hillary Moses Daluz Interview 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 ...
01.31.2022 Episode 243 - New Years Grab Bag 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 ...
12.27.2021 Episode 242 - Review of ASB Documents 2021 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 ...
12.01.2021 Episode 241 - Blind Proficiency Testing Paper 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 ...
10.21.2021 Episode 240 - Todd Weller returns to discuss inconclusives 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 ...
09.27.2021 Episode 239 - 2021 IAI Conference 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 ...
07.06.2021 Episode 238 - Dror and Scurich Article 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 ...
04.25.2021 Episode 237 - Testifying After an Error 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 ...
03.27.2021 Episode 236 - Mindset Paper (Eldridge & Champod, Part Deux!) 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 ...
03.12.2021 Episode 235 - Todd Weller Interview 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 ...
02.27.2021 Episode 234 - Palm Print Black Box Study 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 ...
02.16.2021 Episode 233 - GYRO Accuracy Paper 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 ...
01.06.2021 Episode 232 - Differing Conclusions Article 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, ...
11.24.2020 Episode 231 - Review of Carter, et al. (2020) Paper on Conclusion Scales 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 ...
10.28.2020 Episode 230 - Fingerprint Error Rate in Close Non-Matches 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 ...
10.13.2020 Episode 229 - Bob Garrett 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 ...
09.16.2020 Episode 228 - Knuckle-Crease Daubert Hearing 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 ...
09.02.2020 Episode 227 - NY Firearms Case 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 ...
07.20.2020 Episode 226 - Best Latent Print Books 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 ...
07.01.2020 Episode 225 - The Most Dangerous Animal of All Documentary 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, ...
06.16.2020 Episode 224 - Forensics in the New Normal 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, ...
06.02.2020 Episode 215 - Aging Latent Prints 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 ...
05.24.2020 Episode 223 - Luke Ryan Interview - Mass Drug Scandal Part 3 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 ...
05.06.2020 Episode 222 - How to Fix a Drug Scandal Documentary - Part 2 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 ...
04.29.2020 Episode 217 - Forensic Movie Recommendations during COVID-19 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 ...
04.27.2020 Episode 221 - How to Fix a Drug Scandal Documentary - Part 1 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 ...
04.20.2020 Episode 220 - Blind QC Research at HFSC 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 ...
04.15.2020 Episode 219 - David Camm Case - Part 2 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 ...
04.07.2020 Episode 218 - David Camm Case - Part 1 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 ...
03.19.2020 Episode 216 - OSAC Update and Travel Stories 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 ...
02.24.2020 Episode 214 - Simon Bunter Interview 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? ...
02.04.2020 Episode 213 - Anouk de Ronde Interview 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 ...
01.15.2020 Episode 212 - Activity Level 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 ...
01.08.2020 Episode 211 - OSAC & ASB Update 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 ...
12.15.2019 Episode 210 - Brendan Max Interview 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 ...
12.09.2019 Episode 209 - Friction Ridge Process Map 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 ...
11.29.2019 Episode 208 - Review of Conflict Resolution Paper (Montani, et al.) 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 ...
11.16.2019 Episode 207 - AC Brogdon Interview 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 ...
10.25.2019 Episode 206 - OSAC FRS Standards for Conclusions 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 ...
10.17.2019 Episode 205 - PNW Conference Panel 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 ...
09.23.2019 Episode 204 - 2019 IAI Conference 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 ...
09.16.2019 Episode 203 - FBI Persistency Paper 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 ...
08.21.2019 Episode 202 - Idaho Interviews 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 ...
07.25.2019 Episode 201 - Gaze Detection Article 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 ...
07.11.2019 Episode 200 - Michael Whyte Interview 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, ...
05.11.2019 Episode 199 - Brandon Garrett Interview 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 ...
04.01.2019 Episode 198 - Archie Williams Case 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 ...
03.18.2019 Episode 197 - Review of Miami-Dade Error Rates 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 ...

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