Glenn Langenburg and Eric Ray discuss latent prints, the latest latent print research, forensic science in general, and regular interviews with people in the latent print field.
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 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.
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 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
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 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
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 examiners and similarities and differences between firearms and fingerprints. Lots to cover in an extra-long episode.
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 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):
Link to study results in shinyapp:
Link to confidence interval tools in shinyapp:
Link to error rate primer prepared by Champod, Eldridge, Lambert:
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 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
The hosts are great, and there’s a lot of information regarding fingerprint analysis, even fir the layman. While sometimes it can have jargon that you have to have a bit of experience - either in the field or in forensics in general - it’s still a fascinating look at both the mechanics and the techniques in identification, with specific cases sometimes given as examples.
I really enjoy this show. Thanks!
Great forensic geek podcast
Great podcast for anyone in the field of friction ridge examinations. But they also have quite a few episodes on popular true crime cases which they dissect in detail as only two forensic experts can do. At first I came for the episodes on scholarly papers because, I don’t have time to read them and when I do, I don’t understand them. Glenn and Eric do a great job of making sense of these papers for those of us with common levels of intelligence. But I later found I enjoyed the interview and true crime episodes just as much. Thanks guys, take my 5 stars.