Juror Certainty about Expert Firearms Identification Evidence and the Impact of Cross-examination

Scanlon, Paraic and Banyai, Boglarka and Hart, Ellis and Cooper, Sarah Lucy (2022) Juror Certainty about Expert Firearms Identification Evidence and the Impact of Cross-examination. Southern California Interdisciplinary Law Journal, 31. ISSN 1077-0704

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To evaluate association, firearms examiners compare tool-marks present on suspect ammunition to those present on ammunition test-fired by a suspect weapon. Examiners’ conclusions are generally admissible in US courts, yet the scientific underpinnings of the discipline have been subject to considerable criticism. Cross-examination can be used to bring such criticism to the attention of jurors, who determine the weight of expert evidence. The authors investigated the effect of such cross-examination on juror certainty about expert firearms evidence using online vignettes. A community sample of US participants (n=437) were asked to rate their certainty (0-100) of a forensic match for each of 4 expert statements of certainty, in 2 groups; either with or without a cross-examination highlighting limitations of the tool-mark discipline’s scientific underpinnings. Analysis was undertaken both between groups and between the statements given to each group. Results suggest that cross-examination can have a strong influence on juror decision-making, particularly when experts express their conclusions in certain terms.

Item Type: Article
21 June 2021Accepted
9 February 2022Published Online
Subjects: CAH04 - psychology > CAH04-01 - psychology > CAH04-01-01 - psychology (non-specific)
CAH16 - law > CAH16-01 - law > CAH16-01-01 - law
Divisions: Faculty of Business, Law and Social Sciences > College of Law, Social and Criminal Justice
Depositing User: Sarah Cooper
Date Deposited: 30 Jun 2021 09:36
Last Modified: 11 Feb 2022 10:49
URI: https://www.open-access.bcu.ac.uk/id/eprint/11861

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