Nixing the Judge: Peremptory Challenges of Judges and Strategic Behavior

We examine the usage and impact of peremptory challenges against judges in California courts. Under California law, parties may remove a judge without demonstrating cause by filing a peremptory challenge. No proof or factual basis of bias is required, only a statement indicating that the party believes the judge is prejudiced. The judge cannot contest a timely challenge and is immediately removed from the case. Unlike peremptory challenges for jurors, each side may file only one such challenge. We develop a model in which litigants challenge a judge when the randomly drawn expected replacement is more likely to favor their side. Using data from over 215,000 civil cases in Los Angeles County, we find evidence consistent with strategic behavior: Litigants are more likely to challenge a judge when the replacement is more likely to be against the opponent’s preferences regarding ideology or past rulings on motions.