Pettys — Volume 63, Issue 1

A prominent 2014 study by Epstein, Parker, and Segal concluded that Supreme Court justices exhibit in-group bias in First Amendment free-expression cases, with conservative justices disproportionately supporting conservative speakers. The study received widespread attention when commentators cited it as evidence that the Roberts Court's conservative wing bias affects speech protections. This article provides a detailed critique of the Epstein-Parker-Segal study, examining the methodology, coding decisions, and conclusions. Pettys argues that while the study identifies real phenomena, its conclusions about conservative justices are undercutted by coding errors, superficial case readings, and questionable speaker categorizations. The author contends that the study suffers from the very in-group biases it attributes to the justices—analysts readily embraced conclusions that cast conservative justices unfavorably. Though acknowledging legitimate concerns about judicial ideology, Pettys questions whether the study's specific findings about Chief Justice Roberts and Justice Alito withstand scrutiny, demonstrating how easily even empirical research can reflect researchers' own biases.

Topics: First Amendment · Constitutional Law

Keywords: in-group bias · free speech · Roberts Court · First Amendment · judicial ideology · free expression · Supreme Court