We detect intra-judge variation in judicial decisions driven by factors completely unrelated to the merits of the case, or to any case characteristics for that matter. Concretely, we show that asylum grant rates in US immigration courts differ by the success of the court city’s NFL team on the night before, and by the city’s weather on the day of, the decision. Our data including half a million decisions spanning two decades allows us to exclude confounding factors, such as scheduling and seasonal effects. Most importantly, our design holds the identity of the judge constant. On average, US immigration judges grant an additional 1% of asylum petitions on the day after their city’s NFL team won, relative to days after the team lost. Bad weather on the day of the decision has approximately the opposite effect. By way of comparison, the average grant rate is 39%.
Via Alessandro Cerboni