On Conveying the Probative Value of DNA Evidence: Frequencies, Likelihood Ratios and Error Rates

University of Colorado Law Review, Vol. 67, p. 859, 1996

28 Pages Posted: 10 Jul 2009 Last revised: 17 May 2014

Date Written: 1996

Abstract

Part I of this paper discusses the issue of what the frequencies associated with DNA evidence do and do not mean. Part II describes an alternate way of presenting DNA statistics in court based on Bayesian likelihood ratios. This part also addresses issues associated with identifying the hypothesis of interest and characterizing the evidence. Part III offers a likelihood ratio and estimates its magnitude based on proficiency test data that were analyzed by Koehler, Chia, and Lindsey. Part IV identifies and rebuts arguments that have been offered for ignoring the possibility of error when computing DNA likelihood ratios. Part V considers whether likelihood ratios belong in court and concludes that they may not if experts and jurors do not understand them. Part VI reports an empirical study that compares mock jurors' reactions to various numerical representations of DNA evidence. The results of the study indicate that there are good reasons to suspect that likelihood ratio presentations will confuse jurors.

Keywords: DNA, likelihood rations, Bayesian

Suggested Citation

Koehler, Jonathan J., On Conveying the Probative Value of DNA Evidence: Frequencies, Likelihood Ratios and Error Rates (1996). University of Colorado Law Review, Vol. 67, p. 859, 1996. Available at SSRN: https://ssrn.com/abstract=1432149

Jonathan J. Koehler (Contact Author)

Northwestern University - Pritzker School of Law ( email )

375 E. Chicago Ave
Chicago, IL 60611
United States

Here is the Coronavirus
related research on SSRN

Paper statistics

Downloads
318
Abstract Views
1,231
rank
101,790
PlumX Metrics