Reconsidering the position of jurors with specialist knowledge or expertise

The jury oath requires jurors to return a true verdict according to the evidence. Where a juror happens to have specialist knowledge or expertise in relation to an issue to be determined at trial, the law draws a distinction between the juror applying their own common sense and personal knowledge to the evidence and importing their own specialist knowledge to other jurors. While the former is permitted, the latter is prohibited on the basis that this would introduce extraneous, untested evidence into the deliberations. This distinction places jurors with specialist knowledge or expertise in a difficult position and puts even the most responsible and diligent juror at risk of unconscious jury bias. This chapter explores the jurisprudence on jurors with specialist knowledge or expertise and considers the practicability of this narrow distinction.