CHICAGO (AP) — Chicago’s reputation for police misconduct and brutality shattered relations with the black community long before the federal government announced this week that it was launching a civil-rights investigation of the police department.

The probe was prompted by a video showing a white officer shooting a black teen 16 times and revelations that other officers filed false reports about what happened.

The Rev. Marshall Hatch of New Mt. Pilgrim Missionary Baptist Church says the deep mistrust “becomes a cancer” because it eats away at respect for authority and respect for the law. Some communities, he says, feel like they’re being occupied by police rather than protected by them.

The department first earned a widespread reputation for brutality during the 1968 Democratic National Convention, when officers were seen on television beating demonstrators.