Roger C. Park

The entrapment defense

Most American jurisdictions follow either asubjective or anobjective approach to the entrapment defense. In order to test some of the differences between the two approaches, student jurors viewed a videotaped cocaine trial and were presented with either subjective test or objective test instructions. The admission of prior conviction evidence was also varied. The jurors deliberated, returned a verdict, and then completed a questionnaire that measured their understanding of the instructions and trial facts. Results show that, first, juror comprehension of the principal features of the objective test is very poor. It is suggested that an effort be made to simplify instructions describing the objective test. Should simplification not improve comprehension, it is argued that the judge, not the jury, should decide the entrapment defense when the objective test is used. Second, admission of a prior conviction has a significant impact on verdicts in the subjective test condition, but not in the objective test condition. This finding suggests that the subjective test instructions are effective in encouraging jurors to use prior convictions as evidence of guilt. The content of the objective test instruction may also account for part of the difference in impact. Jurors in the objective test condition were instructed not to take the defendants predisposition into account, and a substantial minority of the jurors under-stood this aspect of the instruction.

Bayes Wars Redivivus - An Exchange

An electronic exchange among 10 evidence scholars that began with a discussion of the restyled Federal Rules and grew into a significant restatement of debates in evidentiary scholarship over the last 50 years, touching on relevance, probative value, inference, Bayesianism and the foundations of evidence, with an introduction by Michael Risinger.

Grand Perspectives on Evidence Law

IN his evidence article, Judge Richard Posner uses a thick version of rational choice theory,2 coupled with a relentless belief in the ex ante effects of evidence rules. This combination entails implicit assumptions about the pervasive knowledge of the rules among the general population, and about the friction-free willingness of actors to change customary ways of doing things in order to obtain an advantage, that are sometimes rather unrealistic.3 As might be expected, Judge Posner also brings to his study of evidence law a sensitivity to costs, trade-offs, and substitutions. I question whether Posners rational choice, ex ante perspective is the best starting point when drawing inferences about the issues