Double Loop Podcast

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...

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 d...

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 cr...

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? Wa...

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...

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...

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 meaningf...

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 Po...

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 ne...

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 vita...

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...

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...

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...

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. Ther...

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 conversati...

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...

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 ju...

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...

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 r...

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 forens...

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 reportin...