The study explored the number of arguments generated by jurors prior to deliberations, the number of arguments introduced during deliberations, and the number of new arguments generated during deliberations. A total of 135 subjects drawn from a college course viewed the tape of a burglary trial. After viewing the tape, subjects were randomly assigned to juries composed of 5, 6, and 12 members. Each subject listed arguments relevant to the case both before and after deliberations. T-tests were used to correlate the number of arguments with jury size. Subjects that served on the large jury produced significantly more arguments as an aggregate before deliberations than did those that served on small juries, and the large jury also produced more arguments during deliberation. The large jury showed a trend toward a greater number of new arguments during deliberation, although the difference was not statistically significant. Implications of the findings for jury decisionmaking are drawn. 17 references.