Lobbying Justice(s)? Exploring the Nature of Amici Influence in State Supreme Court Decision Making

Most studies of amicus influence in both federal and state courts assume that the information provided in these briefs is the mechanism through which amici influence court outcomes. However, the question of how individual state supreme court judges respond to this third-party information and whether or not judicial responses are conditioned by differing methods of judicial retention is rarely theorized. Using social-psychological theories of confirmation bias and motivated reasoning, this article investigates how ideological predispositions and electoral institutions structure the responsiveness of state high-court judges to amicus brief information. Utilizing an original dataset of more than 14,000 votes of state high-court judges across three distinct areas of law, this article tests competing theories of amicus influence to determine how state high-court judges utilize amicus information to render judicial decisions. Results are generally supportive of the informational theory of amicus influence in complex areas of law. However, a conditioning relationship of retention method suggests that competitive elections may alter the mechanism of amicus brief influence such that judicial responsiveness to third-party briefs is more closely tied to the reelection and campaign fundraising considerations of individual judges in politically contentious areas of law.