This article reports on an empirical study of juror comprehension of pattern jury instructions. It demonstrated that comprehension of the original instructions was poor, but that rewriting significantly improved their ability to understand and explain the meaning of the instructions. A separate study showed that jurors report that they discuss and consider the language of the instructions provided to them.
North Carolina Law Review
Walter W. Steele and Elizabeth G. Thornburg, Jury Instructions: A Persistent Failure to Communicate, 67 N.C. L. Rev. 77 (1988)