Re-evaluating how to measure jurors’ comprehension and application of jury instructions

ABSTRACT

In order for jurors to decide a legally correct verdict, they must comprehend and apply jury instructions. To date, empirical research has focused on jurors’ comprehension of instructions. However, it is difficult to know how well jurors actually comprehend instructions, because the tests currently used by researchers to measure jurors’ comprehension provide different estimates of jurors’ comprehension. It is also difficult to know the degree to which jurors apply instructions, because researchers have not directly examined this question. This article reviews the current tests used to measure jurors’ comprehension of instructions, and the current methods used to make inferences about jurors’ application of instructions. It then critically analyses these approaches, and recommends ways to improve these approaches in future research, to enable researchers to draw more precise conclusions about the quality of jurors’ decision-making.

KEYWORDS:

• Jury instructions
• judicial directions
• comprehension
• application
• verdict accuracy
• measurement

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 While these rates of comprehension may not be classified as poor in some contexts, in the jury context, such a classification is appropriate (and widely accepted among researchers in this field), given both the important role of instructions—they tell jurors how to decide the issues in the trial and a legally correct verdict—and the magnitude of jurors’ decision—they decide the defendant’s liberty, and in capital penalty cases, whether the defendant should live or die.

2 The extent to which jurors accept (agree with) the instructions is not relevant, given hypothetical tests explicitly ask jurors to demonstrate whether they can (as opposed to, do) apply instructions.