(September 2020). Unpolluted decisions: Air quality and judicial outcomes in China. Economics Letters, 194, 109369.
Judicial outcomes should not be influenced by factors that have no bearing on legal decisions, but studies have shown that judges can be affected by extraneous variables such as weather, sports events, and food consumption. Employing the universe of drug offense court decisions in five major Chinese cities between 2014 and 2015, we study whether air pollution and temperature affect sentencing outcomes in China, where air pollution is severe and judges have considerable discretion in sentencing drug cases.
We find that Chinese criminal judges are not at all affected by pollution or temperature changes. One standard deviation change in air pollutant PM2.5 level may change the sentence length by no more than 2% of its standard deviation with over 95% probability. Further analysis shows that our results are robust to a variety of specifications and a battery of robustness checks.
Our findings suggest that judicial rulings are not always swayed by extraneous factors, and we discuss conditions under which public officials are more likely to be shielded from these non-legal factors.