Double Loop Podcast

After arguing about the Mandela Effect, Glenn and Eric catch up on some email and discuss ANAB AR3125 7.8.1.2.2 and how this impacts reporting conclusions. Glenn talks about using verbal LRs to express the perceived weight of evidence. Then the guys review a paper from Israel on investigative leads (Attias, et al. 2015) from J of For Sci & Criminology.

Glenn Langenburg and Eric Ray are proud to be joined by Mark Stolorow. Before his years guiding the creation of the OSAC and his days with NIST, he had a varied history getting kicked out of the chemistry department, avoiding the draft, working as a cop, researching blood typing, and wearing plaid jackets. Listen to the interview for all the details of a fantastic career. This episode is sponsored...

Eric Ray and Glenn Langenburg are joined for another episode discussing statistics and probabilities by Professor Christophe Champod from the University of Lausanne. Christophe takes us on a history of his work on fingerprint statistics, his past, current, and future research projects, his hope for the future of statistics in fingerprint comparisons, and how the newest Swiss model is available for...

Eric Ray and Glenn Langenburg interview Australian researcher Gianni Ribeiro at the December 2018 OSAC meeting in Phoenix, AZ. Gianni tells the guys about her research interests studying how juries weigh evidence vs. alibis and other jury studies. She also talks about her impressions of the experts gathered at the OSAC meeting, the discussions going on related to likelihood ratios, and the battles...

Glenn Langenburg and Eric Ray are joined in-person by Henry Swofford as they discuss his career with the Army Crime Lab and the development of FRStat, a model that produces a similarity score between two compared fingerprints and a ratio of how that score fits into same source or different source distributions. The guys discuss why the model was developed, how it's being used, and some of the mode...

Glenn Langenburg and Eric Ray are joined by Cedric Neumann to discuss all things statistical models, probabilities, likelihood ratios, Bayes factors, and more. Cedric discusses his history of research, his history in forensics, and how that's brought him from Switzerland to the UK to the US. This episode is sponsored by IDEMIA and their new Case AFIS product.

Eric Ray and Glenn Langenburg move into a discussion of a new case with the help of special guest Becki Daher. Richard Ramirez, the Night Stalker, terrorized California in the mid-1980's before he has caught with the help of fingerprints and new AFIS technology. Becki Daher was working for the Orange County Sheriff's Office at the time and lifted the fingerprint from the car window that eventually...

Eric Ray and Glenn Langenburg wrap up the final episode in their series on Making a Murderer Season 2 with all of the craziness that didn't fit in all the previous episodes. Doesn't the bloodstain shape mean that he's innocent? Or mean that he's guilty? What about the lack of fingerprints? The burn barrel? The carpet cleaner? The bullet wax? Is Teresa even dead? Is the Double Loop Podcast just ano...

Eric Ray and Glenn Langenburg start to wrap up this second season of Making a Murderer with a discussion of the other new suspects in the case, a bit of internet drama, and the vast Wisconsin conspiracy. They then finally move into the discussion of Brendan Dassey and his ongoing appeals process, and how difficult it is for federal courts to review state court decisions. (This episode is sponsored...

Glenn Langenburg and Eric Ray spend this episode talking about even more of the forensic evidence from the second season of Making a Murderer. They start with a review of the DNA evidence from the hood latch and the bullet fragment. Can there be too much DNA? They also discuss the trace analysis of the bullet fragment, the lack of fingerprints, the mysteries of brain fingerprinting, and even more...

Glenn Langenburg and Eric Ray delve into the second season of Making a Murderer. They start by reviewing the evidence that they had discussed from the first season and then discuss their impressions of the new characters in the docu-series. They then move into a detailed discussion of the experiments conducted by Kathleen Zellner and her new forensic experts on behalf of Steven Avery. The blood an...

Glenn Langenburg and Eric Ray are joined by John Swartz, retired from the Tucson Police Department, for a discussion on the Prime Time Rapist case from the mid-1980's. John talks about how the series of 30 attacks on 90 people affected the Tucson community and the department investigating the crimes. Before the perpetrator could be caught, there was a fingerprint examination error that led to othe...

Eric Ray and Glenn Langenburg begin the episode with a discussion of an article from a law journal by Barbara Spellman titled, Communicating Forensic Evidence: Lessons from Psychological Science. Among her main points are that statistics, likelihood rations, and random match probabilities are terrible ways of communicating information to juries. She goes on to say that there are a number of miscon...

Glenn Langenburg and Eric Ray report on a heated and controversial topic that caught the attention of the latent print world in the summer of 2018, the re-designed IAI Re-Certification test. Every five years, Certified Latent Print Examiners must take a comparison test. The old one was notoriously easy, but that has recently changed, and the error rate was higher than some expected. Carl Speckels...

Glenn Langenburg and Eric Ray interview Teresa Wu from IDEMIA about the new product launch of IDEMIA's Case AFIS. The new system can quickly scan in exemplar prints from any type of standard or non-standard cards which then serve as a mini-database for an AFIS search. Efficiency is vastly improved when the computer takes care of the searching aspect of latent print comparisons. This process can al...

Glenn Langenburg and Eric Ray try to wrap up any final discussion points from The Staircase docu-series. After Michael Peterson's conviction was overturned and a new trial was ordered, new attorneys come in, but an Alford plea is reached and Michael Peterson is released. Should a retrial have gone forward? What decisions did the original judge regret? What mistakes did the prosecution make? What i...

Glenn Langenburg and Eric Ray are graciously joined by Bart Epstein in an interview about bloodstain and other forensic evidence from the trial of Michael Peterson in the death of Kathleen Peterson. Bart Epstein explains his involvement in the case, his opinions on the blood evidence, and where he agreed and disagreed with Duane Deaver and Dr. Henry Lee. This episode is also sponsored by IDEMIA an...

In our second dive down The Staircase, Eric Ray and Glenn Langenburg start looking closely at all of the forensic evidence available in the case and what it all means. The documentary leaves lots of questions that we try to answer in this episode like: Can you trace an impact back to a point in space? Could the wall, rail, or step have caused all of the impact sites? Where was the defense medical...

Eric Ray and Glenn Langenburg focus their forensic science backgrounds on the infamous Kathleen Peterson murder as it was portrayed in The Staircase. The guys review their initial impressions of the case and the documentary and then tell the basic outlines of the story where Michael Peterson is suspected, arrested, charged, and convicted of the murder of his wife. There are so many twists and turn...

Glenn Langenburg and Eric Ray return to the annual IAI conference in San Antonio to talk to attendees about the interesting lectures and workshops that they've seen this year. Morgan Hays from Florida talks about how he stays current with the field as a supervisor and how the exclusion and verification topics were covered at the conference. Do you trust your verifier? Linda Manigault from Nevada t...

Glenn Langenburg and Eric Ray wrap up the three-part discussion on the AAAS Report on the Quality and Gap Analysis of Latent Fingerprint Examination. Surprisingly, the guys agree with many of the recommendations and conclusions in the document with an occasional quibble or clarification. As was hinted in the past two episodes, there are more serious concerns with the report's suggested language an...

Glenn Langenburg and Eric Ray continue the discussion on the pros and cons of the AAAS report. Carey participated with the review of the report and discusses the positive recommendations and the limitations that come from the report not being published in a traditional peer-reviewed journal. After that discussion wrapped up, Carey, Eric, and Glenn get a little off-topic and talk about attending AF...

Glenn Langenburg and Eric Ray finally get around to discussing the report on latent fingerprint comparisons from the American Association for the Advancement of Science. John Black (from Black and White Forensics) was on the committee that wrote the report and joins the discussion on some of the merits and limitations of the paper. While many of the research recommendations are the next steps that...

Glenn Langenburg and Eric Ray are joined by Della Wilkinson from Canada to discuss the final resolution of the Bornyk case from British Columbia. Originally, Judge Funt (see Double Loop Podcast episdoe 10) ruled that the fingerprint evidence would not be admitted after conducting his own study of latent prints and his own comparison. The Crown appealed and a new trial began with the original exami...

Eric Ray sits down for an interview with Simon Cole from the University of California Irvine. Simon explains how he first became interested in forensics and in latent print comparisons in general, and then outlines the history of his criticisms of the field. Glenn Langenburg later joins Eric for a review of the interview and some of Glenn's perspectives on how Simon's criticisms and the latent pri...