Professor Emeritus of Criminology, Law, and Society; Psychological Science; and Law
Ph.D. Stanford University, J.D. University of California, Berkeley
william.thompson@uci.edu
2355 Social Ecology II
Specializations:
forensic science; expert evidence; human judgment and decision making
I am interested in human factors associated with forensic science evidence, including contextual and cognitive bias in forensic analysis and the communication of scientific findings to lawyers and juries. I have written about strengths and limitations of various types of forensic science evidence, particularly DNA evidence, and about the ability of lay juries to evaluate evidence. My work is multidisciplinary, it involves law, psychology, various areas of biology (particularly genetics and molecular biology), and statistics.
Recent Activities
Maryland Attorney General’s Audit Design Team — I co-chaired a committee that designed and carried out a first-of-its-kind study to investigate allegations of racial and pro-police bias in Maryland’s medical examination system. Our report was released May 15, 2025 and is available here.
Royal Statistical Society — I served on the RSS panel that drafted the report: Healthcare Serial Killer or Coincidence? Statistical issues in investigation of suspected medical misconduct (Septemter, 2022).
Special Master for the United States District Court, District of Minnesota. I assisted in a Daubert hearing on the admissibility of STRMix, a program for probabilistic genotyping. My report on the scientific status of STRMix informed rulings of the Magistrate Judge and the District Court Judge.
Recent Publications
Thompson, W.C. (2023). Shifting decision thresholds can undermine the probative value and legal utility of forensic pattern-matching evidence. Proceedings of the National Academy of Sciences, USA, 120(41): e2301844120e.
Thompson, W.C. (2023). Uncertainty in probabilistic genotyping of low template DNA: A case study comparing STRMix™ and TrueAllele™ Journal of Forensic Sciences, 68(3): 1049-1063. [One of the ten most frequently cited articles published by this journal in 2022 and 2023]
Comments on above article by John Buckleton and colleagues: Published version; open access version
My response to Buckleton et al.
Comments on the above article by Mark Perlin and colleagues
My response to Perlin et al.
Copies of some additional publication can be found on my SSRN Author’s Page.
Videos of Public Lectures
AAAS Meeting 2022
Interview with Jeff Kukucka on “The Ubiquity of Unintentional Biases in Forensic Analysis”
Stetson College of Law Forensic Science Webinar Series
September 16, 2019: Latent Fingerprint Essentials
CSAFE Webinar
November 2017: How Should Forensic Scientists Present Source Conclusions
Isaac Newton Institute for Mathematical Sciences, University of Cambridge
November 8, 2016: Elicitation of Priors in Bayesian Modeling of DNA Evidence
September 29, 2016: Using Bayesian Networks to Analyze What Experts Need to Know (and When they Know Too Much)
August 31, 2016: Lay Understanding (and Misunderstanding) of Quantitative Statements about the Weight of Forensic Evidence
NIST Technical Colloquium: Quantifying the Weight of Forensic Evidence
May 12, 2016: Lay Reactions to Quantitative Statements About the Weight of Forensic Science Evidence
NIST International Forensic Symposium: Forensic Science Error Management
July 24, 2015: Plenary Presentation (Day 4 Morning General Session): What is the Proper Evidentiary Basis for a Forensic Science Opinion?
Podcasts
Interview with Statistician John Bailer of Miami University on the Podcast Stats + Stories.
Interview with Vanderbilt Law School Professor Edward Cheng for the Podcast Excited Utterance
Video Training Materials for Lawyers
Understanding Forensic Statistics
Part I: Quantification
Part II: Classification
Part III: Comparison/Identification
OJ Simpson Trial–Background Materials
The Netflix documentary American Manhunt: O.J. Simpson (2025), which included interviews with me, prompted many questions and comments about the DNA evidence that incriminated OJ Simpson in his 1995 criminal trial and how it was challenged by Simpson’s defense lawyers. This article, originally published in the University of Colorado Law Review in 1996, offers a detailed account of those matters.