Fair Numbers of Peremptory Challenges in Jury Trials

Abstract We propose a model for determining the appropriate number of peremptory challenges for each party to a jury trial to ensure fairness. We suppose that all jurors not removed for cause may be thought of as in one of three categories: biased against the prosecution/plaintiff, biased against the defense, and fair. We propose that a fair number of peremptory challenges for a side is that number sufficient to challenge all jurors biased against it, with a certain probability. Given estimates for the various parameters in the model, an exact algorithm, and an approximation are proposed and illustrated.