Citation

Martire KA, Edmond G, Navarro DJ, Newell BR. Sci. Justice 2017; 57(1): 76-79.

Affiliation

School of Psychology, The University of New South Wales.

Copyright

(Copyright © 2017, Forensic Science Society, Publisher Elsevier Publishing)

DOI

10.1016/j.scijus.2016.10.004

PMID

28063591

Abstract

The assignment of personal probabilities to form a forensic practitioner's likelihood ratio is a mental operation subject to all the frailties of human memory, perception and judgment. While we agree that beliefs expressed as coherent probabilities are neither 'right' nor 'wrong' we argue that debate over this fact obscures both the requirement for and consideration of the 'helpfulness' of practitioner's opinions. We also question the extent to which a likelihood ratio based on personal probabilities can realistically be expected to 'encapsulate all uncertainty'. Courts cannot rigorously assess a forensic practitioner's bare assertions of belief regarding evidential strength. At a minimum, information regarding the uncertainty both within and between the opinions of practitioners is required.

Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

Language: en