"It's possible that there was an increase in spread [of the virus] among those who attended the protests... but protests may have made others more reluctant to leave their homes."

"If the protests are perceived to be dangerous (because of property destruction, violent response from police or potential for infection), that can cause people who do not attend to increase their social distancing and sheltering-at-home behaviors, said Dhaval Dave, a professor of economics at Bentley University in Massachusetts and co-author of the study. But even rates of infection among protesters who got tested in pop-up clinics is proving to be low, Dave said, suggesting that many are using effective protective measures like wearing masks and attempting to social distance as much as a person is able."

From "Coronavirus is spreading so fast among Wisconsin 20-somethings that the CDC came to investigate. Is it protests? Bars? Here's what we know" in the Appleton Post-Crescent.

See? The violence might have helped, because it was one more reason to shelter at home. I was going to say a few more sarcastic things about violence, but it's the Era of That's Not Funny, and there wasn't one of them that I wasn't afraid could be taken seriously.