Compared to what? How are we classifying "more violent"?
Towards everyone in general? Or just the minorities they lynched/allowed to be lynched back in the day?
Was it less violent when each police precinct was literally owned/controlled by a different political ward leader--used to attack and intimidate political opposition? What about when the police were basically just used to bust unions, and also to keep all of the Irish/German/Catholics/immigrants/etc. in line? What about when police were literally just slave patrols--was that less violent?
Yes, the 80s basically saw cities turn into literal war zones, but that just meant a different kind of violence. And honestly that's also when people really started tracking the stats -- so there's not much to compare it to, although if you can find police numbers (shootings, LODDs, assaults, etc.) prior to the 80s I'd be genuinely interested in reading about them.