“Laughter in Supreme Court oral arguments has been misunderstood, treated as either a lighthearted distraction from the Court’s serious work, or interpreted as an equalizing force in an otherwise hierarchical environment. Examining the more than 9000 instances of laughter witnessed at the Court since 1955, this Article shows that the justices of the Supreme Court use courtroom humor as a tool of advocacy and as a signal of their power and status. As the justices have taken on a greater advocacy role in the modern era, they have also provoked an increasing level of laughter.The performative nature of courtroom humor is apparent from the uneven distribution of judicial jokes, jests, and jibes. The justices overwhelmingly direct their most humorous comments at the advocates who they disagree with, the advocates who are losing, and at novice advocates. Building on prior work, we show that laughter in the courtroom is yet another aspect of judicial behavior that can be used to predict cases before justices have even voted. Many laughs occur in response to humorous comments, but that should not distract from the serious and strategic work being done by that humor. To fully understand oral argument, Court observers would be wise to take laughter seriously.”