Sandys, M., & Dillehay, R. C. (1995). First-ballot votes, predeliberation dispositions, and final verdicts in jury trials. Law and Human Behavior, 19, 175-195.
This study examines the proposition that first ballots predict jury verdicts inaactual juries, an oft-cited finding from Kalven and Zeisel, and the explicit assumption by Kalven and Zeisel that first-ballot preferences are equivalent to predeliberation opinions, referred to as the liberation hypothesis. Interview data from respondents who had served on felony juries indicate that first ballots do predict jury verdicts at a high level. However, it is probable that influence occurs in juries prior to the first ballot, making it unlikely that the distribution of votes on the first ballot is equivalent to the individual inclinations of jurors at the time they enter into deliberation, which casts doubt on the liberation hypothesis. Methodological issues in the study of real juries on these topics are discussed.
Very few deliberations verdict-driven; most evidence-driven or a mix of the two. Final verdicts consistent with 1st-ballot majorities 89% of the time. No evidence of leniency in evenly split juries. Predictive validity of 1st ballot weaker when no discussion had taken place.