Research on probabilistic reasoning has discovered several systematic errors, among which base rate neglect and the fallacy of the transposed conditional have featured prominently. This article introduces the term miss rate neglect to capture the systematic failure to properly account for false positives, i.e. the probability of evidence (E) given the hypothesis (H) is false, P(E|~H). Miss rate neglect occurs when decision makers (i) completely disregard the miss rate; (ii) underestimate the importance of differences in the miss rate, or (iii) overlook circumstances that affect the miss rate. We explain the relevance of miss rate neglect for legal decision making, review extant literature, present new experimental work that empirically validates options (ii) and (iii), and propose experimental variations that future research may pursue.

The problem of ‘naked statistical evidence’ is one of the most debated issues in evidence theory. Most evidence scholars agree that it is deeply problematic to base a verdict on naked statistical evidence, but they disagree on why it is problematic, and point to different characteristics of naked statistical evidence as the root of the problem. In this article, the author discusses the merits of different solutions to the problem of naked statistical evidence, and argues for the incentive-solution: verdicts based on naked statistical evidence are unacceptable as they do not contribute in a positive way to the incentive structure for lawful behaviour.

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Although legal contexts are subject to biased reasoning and decision making, to identify and test debiasing techniques has largely remained an open task. We report on experimentally deploying the technique "giving reasons pro et contra" with professional ( N = 239) and lay judges ( N = 372) at Swedish municipal courts. Using a mock legal scenario, participants assessed the relevance of an eyewitness's previous conviction for his credibility. On average, both groups displayed low degrees of bias. We observed a small positive debiasing effect only for professional judges. Strong evidence was obtained for a relation between profession and relevance-assessment: Lay judges seemed to assign a greater importance to the prior conviction than professional judges did. We discuss challenges for future research, calling other research groups to contribute additional samples.

The authors investigate to what extent an evaluation of legal evidence in terms of coherence (suggested by Thagard, Amaya, Van Koppen and others) is reconcilable with a probabilistic (Bayesian) approach to legal evidence. The article is written by one author (Dahlman) with a background in the bayesian approach to legal evidence, and one author (Mackor) with a background in scenario theory. The authors find common ground but partly diverge in their conclusions. Their findings give support to the claim (reductionism) that coherence can be translated into probability without loss. Dahlman therefore concludes that the probabilistic vocabulary is superior to the coherence vocabulary, since it is more precise. Mackor is more agnostic in her conclusions about reductionism. In Mackor's view, the findings of their joint investigation do not imply that the probabilistic approach is superior to the coherentist approach.