Do judicial assignments matter? Evidence from random case allocation

Because judges exercise discretion in how they handle and decide cases, heterogeneity across judges can affect case outcomes and, thus, preferences among litigants for particular judges. However, selection obscures the causal mechanisms that drive these preferences. We overcome this challenge by studying the introduction of random case assignment in a venue (the U.S. District Court for the Western District of Texas) that previously experienced a high degree of case concentration before one judge (Alan Albright), whom litigants could select with virtual certainty. To assess Albright's importance to patent enforcers, we examine how case filing patterns changed following the adoption of random case allocation and show that case filings in the Western District of Texas decreased significantly at both the intensive and extensive margins. Moreover, to shed light on why litigants prefer Judge Albright, we compare motions practice and case management metrics across randomly assigned cases and show that cases assigned to Albright were both scheduled to proceed to trial relatively quickly and less likely to raise the issue of patentable subject matter.