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

Episode 231 - Conclusion Scales Article

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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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

The TFSC Report and the Webster Case - Pt 2

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 Report

https://www.txcourts.gov/media/1457617/fir-complaint-2216-rsa-latent-prints-as-of-12623.pdf

Episode 269 - The TFSC Report and the Webster Case - Pt 1

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.

Episode 268 - Steve Johnson Interview

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

Episode 267- Chloe George Interview - Research on Phalange Patterns

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.

Episode 231 - Conclusion Scales Article

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