Bayes to Bench: Understanding Likelihood Ratios and Probabilistic Genotyping from Foundations to Legal Challenges

Home » Bayes to Bench: Understanding Likelihood Ratios and Probabilistic Genotyping from Foundations to Legal Challenges

Workshop

Bayes to Bench: Understanding Likelihood Ratios and Probabilistic Genotyping from Foundations to Legal Challenges

October 26, 2026 //
8:00 am -
4:00 pm //
Rhode Island Convention Center

Description:

Forensic laboratories have increasingly adopted probabilistic genotyping (PG) methods for the interpretation of DNA mixtures. Statistical evaluations of PG results use the Likelihood Ratio (LR).

Legal challenges at admissibility hearings span a range of topics. We will focus on four key areas: the scope of the internal validation (“factor space”), the assigned number of contributors, relatives and the Likelihood Ratio.

Part one of this workshop will build foundational understanding of Bayes Theorem and the LR, its use within forensic DNA interpretation, and explanation in court. Part two will address three common challenges to the use of PG. We will discuss experimental design and summarize published material addressing the key issues.

Handouts will be provided.

Learning Outcomes:

To gain a robust foundation in Bayes Theorem and the LR and be able to explain it.
Support you and your laboratory to effectively address common challenges to the use of Probabilistic Genotyping – relatives, “factor space”, and number of contributors.
Develop practical skills to communicate probabilistic genotyping results and likelihood ratios clearly and confidently in court, including strategies for addressing admissibility challenges.

Intended Audience:

This workshop is intended for DNA analysts, supervisors, technical leaders, attorneys and judges. Suitable for those just beginning.

Description:

Forensic laboratories have increasingly adopted probabilistic genotyping (PG) methods for the interpretation of DNA mixtures. Statistical evaluations of PG results use the Likelihood Ratio (LR).

Legal challenges at admissibility hearings span a range of topics. We will focus on four key areas: the scope of the internal validation (“factor space”), the assigned number of contributors, relatives and the Likelihood Ratio.

Part one of this workshop will build foundational understanding of Bayes Theorem and the LR, its use within forensic DNA interpretation, and explanation in court. Part two will address three common challenges to the use of PG. We will discuss experimental design and summarize published material addressing the key issues.

Handouts will be provided.

Learning Outcomes:

To gain a robust foundation in Bayes Theorem and the LR and be able to explain it.
Support you and your laboratory to effectively address common challenges to the use of Probabilistic Genotyping – relatives, “factor space”, and number of contributors.
Develop practical skills to communicate probabilistic genotyping results and likelihood ratios clearly and confidently in court, including strategies for addressing admissibility challenges.

Intended Audience:

This workshop is intended for DNA analysts, supervisors, technical leaders, attorneys and judges. Suitable for those just beginning.

Pricing:

Standard Registration$425

Fees include printed workshop materials, breakfast, lunch, and breaks

Workshop currently at capacity. A waitlist is available to join on our registration page.

Chair

Michael Coble

Professor and Executive Director, Center for Human Identification (CHI), University of North Texas Health Science Center

Michael Coble, PhD, is a Professor and the Executive Director of the Center for Human Identification at the University of North Texas Health Fort Worth. Dr. Coble received his PhD in Genetics from The George Washington University. He has over 100 peer-reviewed publications in forensic DNA analysis and interpretation and is recognized among the top 2% of highly cited researchers worldwide.

Jo-Anne Bright

PHF Science

Jo-Anne Bright is a Senior Science Leader within the Forensic Biology group at PHF Science, where she has worked since 1999. Jo is one of the co developers of STRmix™, expert software for the interpretation of forensic DNA profiles and the new Australasian standard.

Richard Wivell

PHF Science

Richard Wivell is a Senior Scientist within the STRmixTM team at PHF Science, New Zealand where he has worked since 2008. Before moving to New Zealand, Richard was a Forensic Scientist for the Metropolitan Police Service and the Forensic Science Service in the UK.

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