City records show that Mr. Slager, who joined the Police Department in 2010, was the subject of a complaint over use of force in September 2013. In that episode, according to city records, Mr. Slager was investigating a burglary when he used his Taser device to stun a man who the authorities said did not comply with directions. Mr. Slager was cleared of wrongdoing. Police officials upheld a complaint against Mr. Slager this year, after a woman said he refused to write a report in a harassment case.

Located just up Interstate 26 from Charleston, a haven of tourism and commerce along the South Carolina coast, North Charleston is a city of competing identities. Some neighborhoods are suburban sanctuaries filled with palmetto trees, late-model cars and spotless restaurants. Others are deeply impoverished, where blocks are dominated by pawn shops and convenience stores.

The poverty rate here — more than 23 percent — is 5.3 percentage points higher than the rate statewide. But much of the talk here is about the crime and the policing strategies intended to combat it.

Rashard Brown, 30, said he had been pulled over twice in less than two months, including one instance when an officer trailed him for about three miles. “If I broke down on the side of the road with a flat tire, he’d ride right past like he didn’t even see me,” he said. “But if I look like I’m riding clean and I’ve got a lot of money, next thing you know you’ve pulled me over and you stick your head in the car, smell and see what’s going on and see if you see anything.”

Doris Brown, who lives in Charleston but owns a hair salon in North Charleston, said she, too, was pulled over for a broken taillight but believed she may have been stopped because she was a black woman driving a luxury car. “After I left, my friend went behind and there was nothing wrong with my taillight,” she said. “Everything was working with my car, so I felt as though I was being profiled.”