[E. Pluribus Unum]

Violent crime increases to a point not because of the heat, but because people spend more time outside interacting with each other, providing more opportunity for violent crime to occur.

When it gets too hot they start staying inside and crime goes down.

The Hazy Science of Hot Weather and Violence

[heartwood]

A lot of violent crime is domestic and under-reported so being cooped up with your nearest and dearest may not be good as it looks.

From what studies I’ve seen crime rises over 80 and drops after 90 when people retreat inside. Now in the old days when air conditioning wasn’t common, days over 90 were probably bad days.