Cruel and Unusual Punishment

<h3>Abstract</h3> Prison temperatures in the southern United States frequently exceed dangerous heat index levels and lack temperature controls. Using a unique daily panel of prisoner incidents from correctional facilities spread across the state of Mississippi, a system without air conditioning, we show that hot days increase both the rates and probabilities of severe violent acts by prisoners by approximately 20%. The effects of heat appear neither cumulative nor the result of temporal displacement. These results help inform constitutional concerns of incarceration in extreme temperatures, and document a potentially growing social cost of shifting climate.