Dateline: August, 2010, Issue 4
Jurors are given jury instructions, and may use those instructions as they see fit during deliberations. Some juries discuss the instructions extensively, while other juries do not.
How much time do jurors spend discussing jury instructions? With the cooperation of the Wyoming courts, Saxton (1998) gave questionnaires to jurors when they were discharged from service on actual trials. Jurors reported that they had spent around 31% of the time during deliberations discussing the instructions.
These discussions did not ensure comprehension of the instructions. While 97% of jurors believed that they understood the instructions "pretty well" or "completely," when jurors were asked true/false questions about specific legal rules on which they had been instructed, only about 70% of their responses were correct.
Instructions and jury deliberations, by themselves, are insufficient to ensure juror understanding of jury instructions.
Source Saxton, B. (1998). How well do jurors understand jury instructions? A field test using real juries and real trials in Wyoming. Land & Water Law Review, 33, pp. 59-189.