We document judicial leniency on defendant birthdays across 5 million decisions. French sentences are 1% fewer and 3% shorter. U.S. federal sentences are 33% shorter in the day component of sentences (the month component remains unaffected). New Orleans sentences are 15% shorter overall. No leniency appears on the days before or after a defendant’s birthday. Federal judges using deterrence language in opinions, are unaffected, isolating the judicial as opposed to defendant channel. The effect is doubled when judge and defendant share the same race. Our courtroom setting rules out many models of social preferences with reciprocity motives.
IAST working paper, n. 18-76, 2018