Heather MacDonald has this op-ed in the WSJ with the above title.  The subtitle is "The consequences of the 'Ferguson effect' are already appearing. The main victims of growing violence will be the inner-city poor."  Here are the concluding paragraphs:

Contrary to the claims of the "black lives matter" movement, no government policy in the past quarter century has done more for urban reclamation than proactive policing. Data-driven enforcement, in conjunction with stricter penalties for criminals and "broken windows" policing, has saved thousands of black lives, brought lawful commerce and jobs to once drug-infested neighborhoods and allowed millions to go about their daily lives without fear.

To be sure, police officers need to treat everyone they encounter with courtesy and respect. Any fatal police shooting of an innocent person is a horrifying tragedy that police training must work incessantly to prevent. But unless the demonization of law enforcement ends, the liberating gains in urban safety over the past 20 years will be lost.