Presenter: Keira M. Cook

Faculty Sponsor: Martha Yoder

School: UMass Amherst

Research Area: Law and Legal Studies

Session: Poster Session 1, 10:30 AM - 11:15 AM, Concourse, B11

ABSTRACT

The Sixth Amendment guarantees criminal defendants the right to trial by an “impartial jury,” a principle the Supreme Court has long treated as foundational to fair adjudication. Yet the Court’s doctrine rests on implicit assumptions about juror cognition, namely, that bias can be identified and corrected through introspection, self-report, and traditional adversarial safeguards such as voir dire and cross-examination. This thesis argues that these assumptions reflect an outdated model of human rationality.

Drawing on contemporary cognitive psychology, memory research, and epistemology, this project demonstrates that bias, heuristic reasoning, and confidence inflation are predictable features of ordinary cognition rather than departures from it. Research on dual-process theory and reconstructive memory reveals that many influences shaping juror decision-making operate automatically and are often inaccessible to conscious reflection. Consequently, constitutional doctrine that relies on jurors’ self-assessments of impartiality may misapprehend the cognitive realities of belief formation.

Through analysis of Smith v. Phillips, Manson v. Brathwaite, Perry v. New Hampshire, and Pena-Rodriguez v. Colorado, this thesis identifies the Court’s operative conception of impartiality as both procedural safeguard and cognitive assumption. It contends that the meaning of “impartial jury” must be reevaluated in light of established cognitive limitations and reconceived as a structural constitutional guarantee.