Memphis is a majority African American city. The current mayor is the first white mayor after 24 years of African American mayors. The police department is majority African American and has a female African American police chief.
There's something going on but race doesn't fit.
Memphis has a high crime rate.
The Arkansas national guard was sent to west Memphis to assist the police if violent protests spilled over the border. They did shut down the I40 bridge across the Mississippi for a while.
I think our weather has suppressed protests. Freezing or near freezing rain is miserable.