Overview

The Federal Bureau of Investigation Laboratory has partnered with the National Institute of Justice’s Forensic Technology Center of Excellence to create a series of online workshops aimed at increasing knowledge, understanding, and the reliable application of probabilistic genotyping to evidentiary DNA typing results. Targeting DNA scientists in the forensic laboratory and legal professionals hearing DNA evidence in court, lectures begin with fundamental information and increase in complexity to address a variety of topics relevant to the development and use of probabilistic genotyping in criminal investigations, from the laboratory to the courtroom.

We begin by covering fundamental aspects of interpreting DNA results, as well as factors that impact DNA typing results, such as the transfer and persistence of DNA on evidence and stochastic effects. Particular consideration is given to the interpretation of low-template evidence, as exemplified in the Amanda Knox case.

The tenets of probabilistic genotyping are introduced, including statistical aspects and mechanisms of computer-assisted analysis. Lecturers walk you through the reasoning behind setting propositions that reflect case scenarios and whether, say, a suspect left the DNA on the evidence. Likelihood ratios are calculated and discussed. Three fully continuous software systems will be presented by the respective developers, with the goal of enabling participants in the session to understand the features, basic functioning, capabilities, and limitations of the software programs.

Lecturers will also share their experience in validating probabilistic genotyping systems, noting particular studies that were critical to the development of standard operating procedures within their laboratories. They will discuss research and data generated in the course of validation studies that were used to assess uncertainty and limitations of the software.

Historically, the predominant means of assigning statistical weight to many DNA mixtures in the U.S. has been the combined probability of inclusion, or CPI. Accordingly, many forensic DNA analysts, as well as attorneys and judges, are well-versed in the CPI as a match probability. In this series, we devote two sessions to helping DNA analysts and legal professionals to understand degrees of statistical weight and properly communicate likelihood ratios and their meaning. The SWGDAM recommendations for reporting likelihood ratios will be discussed, along with an explanation of the empirical basis for its verbal scale that may be used in reports and testimony along with the likelihood ratio. Participants’ ears will be tuned to lines of questioning that could lead to a fallacious statement about the statistic. The U.S. Department of Justice Uniform Language for Testimony and Reporting will be imparted.

The status of probabilistic genotyping in U.S. courts will be detailed, including its use in criminal proceedings and admissibility hearing outcomes. Representatives of STRmix™ and TrueAllele® will share examples of successful case outcomes and issues addressed in court.

The series is comprised of the modules listed below. You will have the opportunity to pose questions to the lecturers during each session. A tentative overflow session is designated as a conclusion to the series.

Please re-visit for updates and additional detail. Scientific literature citations will be posted as encouraged reading!


Module 1: May 1, 2019
The Elements of DNA Profile Interpretation and Probabilistic Genotyping
Lynn Garcia – Texas Forensic Science Commission, Austin, Texas
Peter Gill – University of Oslo, Oslo, Norway
Tamyra Moretti – Federal Bureau of Investigation, Quantico, Virginia
Learn more here.

 


Module 2: May 8, 2019
Statistical Genetics and the Mechanisms of Probabilistic Genotyping
David Balding – University of Melbourne, Melbourne, Australia
John Buckleton – Institute of Environmental Science and Research, Auckland, New Zealand
Michael Coble – University of North Texas Health Science Center, Fort Worth, Texas
Steven Myers – California Department of Justice, Richmond, California
Learn more here.

 


Module 3: May 22, 2019
Probabilistic Genotyping Software and Output
Michael Coble – University of North Texas Health Science Center, Fort Worth, Texas
Peter Gill – Oslo University, Oslo, Norway
Tamyra Moretti – Federal Bureau of Investigation, Quantico, Viriginia
Mark Perlin – Cybergenetics, Pittsburgh, Pennsylvania
John Buckleton – Institute of Environmental Science and Research, Auckland, New Zealand
Learn more here.

 


Module 4: May 29, 2019
Validation of Probabilistic Genotyping Systems for Casework Usage
Tamyra Moretti – Federal Bureau of Investigation, Quantico, Virginia
Sarah Noël – Laboratoire de Sciences Judiciaires et de Médecine Légale, Montreal, Canada
Duncan Taylor – Forensic Science South Australia, Adelaide, Australia
Learn more here.

 


Module 5: June 12, 2019
Representation of Statistical Weight to Stakeholders and the Court
David Kaye – Penn State University School of Law, University Park, Pennsylvania
Tamyra Moretti – Federal Bureau of Investigation, Quantico, Virginia
Steven Myers – California Department of Justice, Richmond, California
Learn more here.

 


Module 6: June 19, 2019
Probabilistic Genotyping in Court
John Buckleton – Institute of Environmental Science and Research, Auckland, New Zealand
Jerrilyn Conway – Federal Bureau of Investigation, Quantico, Virginia
Dawn Herkenham
– Leidos, Alexandria, Virginia
Mark Perlin – Cybergenetics, Pittsburgh, Pennsylvania
Learn more here.

 


Module 7: June 26, 2019
Uncertainty and Limitations of Probabilistic Genotyping Systems
Amke Caliebe – University of Kiel, Kiel, Germany
Zane Kerr – Institute on Environmental Science and Research, Auckland, New Zealand
Klaas Slooten – Netherlands Forensic Institute & Vrije University, Amsterdam, The Netherlands
Bianca Szkuta – Victoria Police Forensic Services Department & Deakin University, Geelong, Australia
Learn more here.

 


Module 8: July 17, 2019
Probabilistic Genotyping Summation and Special Topics
John Buckleton – Institute of Environmental Science and Research, Auckland, New Zealand
Jo-Anne Bright – Institute of Environmental Science and Research, Auckland, New Zealand
Ted Hunt – Attorney, U.S. Department of Justice, Washington, D.C.
Klaas Slooten – Netherlands Forensic Institute & Vrije University, Amsterdam, The Netherlands
Learn more here.