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.

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

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

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.

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.