Abstract: | Is the decision-making of Supreme Court justices influenced by extraneous factors beyond law and policy? We explore this question by examining attorney-induced laughter during oral arguments in cases heard by the Court. Drawing on theories of political psychology and social cognition, we posit that laughter serves as a positive affective cue that might favorably dispose justices (albeit subconsciously) to the side causing the laughter. Analyzing oral argument transcripts during the 1986–93 terms, we find that the side causing more instances of laughter is more likely to win the votes of individual justices, even while controlling for other legally and politically relevant factors. We further find that the effect of laughter is conditional—it exerts a heightened persuasive power on ideologically congruent justices, in noncomplex cases, and when the legal argumentation is of higher quality. Our research thus contributes to the growing literature on personal and emotional aspects of judicial decision-making and, specifically, the emerging scholarly interest in the role of humor during Supreme Court oral arguments. |