Abstract
Validity of the Juror Bias Scale in relation to mock jury decisions. In the present study, the validity of the Spanish adaptation of Juror Bias Scale (JBS, Kassin & Wrightsman, 1983), is tested in relation to its capability to predict the group decisions (verdicts and verdict's object questions) reached by different groups of juries composed by subjects previously classified by the JBS as "defense-biased" or "prosecution-biased". Judicial simulations are used to develop the study, in which the strength of evidence is manipulated and the type of case and the presentation format are kept constant. To analyze data exact inference methods are used. The results indicated that, under ambiguity condition, the JBS scores successfully predict the group verdicts of both defense-biased and prosecution-biased juries, as well as the verdict's object questions with "opinion character". Implications of these results are discussed in relation to the importance of individual biases in group decisions and the utility of this type of scales in jury selection.
