When the application of res judicata involves factual disputes, the jury must be the judicial actor to resolve these discrepancies. The fact-law distinction, which gives questions of fact to the jury and questions of law to the judge, has guided American courts for hundreds of years. From the time of the adoption of the Seventh Amendment until the end of the nineteenth century, courts have viewed res judicata disputes as factual determinations within the province of the jury.The migration from question of fact to question of law in the twentieth century lacked any proffered legal justification, and even as the courts proclaimed res judicata as distinctively within the judge’s dominion, they still acknowledged the factual nature of the res judicata inquiry. Even the judicial screening doctrine and modern Seventh Amendment jurisprudence cannot justify holding res judicata as a question of law. Thus, although state and federal courts hold res judicata as a question of law, there is no legal justification for doing so. By trying the preclusion claim separately in a bifurcated trial, courts protect litigants’ constitutional right to a jury trial.
Madrid, Steven J., "Annexation of the Jury's Role in Res Judicata Disputes: The Silent Migration from Question of Fact to Question of Law" (2012). Cornell Law Library Prize for Exemplary Student Research Papers. Paper 4.