But putting those new officers on the streets could take years, as could a return — if ever — to a pre-Ferguson era, said University of Missouri-St. Louis criminologist Rick Rosenfeld. Rosenfeld looks back at race riots that broke out in Cincinnati about 12 years ago, after a series of police shootings involving white officers and young black men, to gauge what may be happening here.

“There, officials concluded that officers simply weren’t being as aggressive in stopping and questioning people and making arrests,” Rosenfeld said. “I don’t know if that’s happening in St. Louis, but it wouldn’t be a complete surprise given Cincinnati’s history.”

CRIME UP, ARRESTS DOWN

At the end of July, St. Louis’ overall crime rate was down more than 12 percent compared with the same period in 2013. By the end of October, it was down only about 8 percent.

Some crimes continued to trend downward after July, according to figures for Aug. 1 through Oct. 31. But crimes against persons were up almost 10 percent, as were burglaries.