Lawrence Crosby, a doctoral student at Northwestern University, was thrown to the ground after being pulled over by police on Oct. 10, 2015. A woman had called 911 saying it looked like he was stealing his car. (Evanston Police Department)

Pinned to the ground by officers who kneed and struck him, Lawrence Crosby screamed whatever he could think of to convince them that he was a law-abiding PhD student, not a violent car thief.

“This is my vehicle, sir,” he said, his voice captured by the dashboard-camera video. “I have evidence. . . . I purchased this vehicle Jan. 23, 2015, from Libertyville Chevrolet.”

It wasn’t enough. The officers placed him in handcuffs in the driveway of a church, two blocks from the police station in Evanston, Ill.

Police released the dash-cam video earlier this week, detailing the half-hour encounter that sparked a civil lawsuit from Crosby and a discussion about race and policing in this city of 75,000, just north of Chicago.

The video includes footage from the dash cam of one of the officers involved in the altercation. But it’s also synced with video of a personal dash cam Crosby kept running in his car.

On that night in October 2015, Crosby was headed to Northwestern University, where he was studying for his doctoral degree in civil engineering.

But something was wrong with the molding on his car, so he pulled out a metal bar to try to fix the strip on the roof, he says on the video.

A woman passing by saw him — a black man, wearing a hoodie, with some kind of bar pressed up against a car.

She picked up the phone and called 911, telling the dispatcher she thought she was witnessing a car break-in.

“He had a bar in his hand, and it looked like he was jimmying the door open,” she told the dispatcher.

When Crosby drove off, the woman followed his Chevrolet and relayed information about his location to police.

Crosby was on the phone as he drove, and communicated his growing unease. He realized the situation could look suspicious to a passerby and hoped it didn’t escalate.

“It was a little bit dark,” he says to someone while on the phone, captured on video. “You know how it is with black people — they think we’re always trying to do something wrong.”

He noticed the car following him, and told the person on the other end of the phone that he’s going to head to a place where he’ll be safe.

“I think this person is still following me,” he says. “I think they’re trying to play some games. I’m about to go to the police station now.”

He never makes it. Two blocks from the police station, an officer pulls behind his car and puts on his blue lights.

Crosby stops the car in the driveway of a church, and slowly gets out facing the officers, hands in the air.

He begins to explain, but the officers order him to keep his hands up. Others scream at him to get on the ground.

He turns and, in an instant, five officers sprint toward him. They drive him back several feet, kneeing him to force him to the ground and striking him with open hands to make him comply, a police spokesman said later.

“Stop resisting,” an officer yells as another strikes Crosby’s thigh.

“I’m cooperating. I’m cooperating,” Crosby replies.

He continues to explain that the car is his, where he got it from and when. He attends Northwestern and is a civil engineering PhD, he says. He was just trying to fix his car.

He asks the officers why he’s being handcuffed; they say they have to figure out who the car belongs to.

They determine it’s his, but he was still arrested and charged with disobeying officers and resisting arrest. A judge later threw out the charges, Crosby’s attorney Tim Touhy, told the Chicago Tribune.

The officers were never charged or disciplined. The Evanston Police Department has defended their actions.

Crosby, who couldn’t be reached for comment Saturday, filed a civil lawsuit in 2016.

Evanston Alderman Brian Miller, who is running for mayor, told The Washington Post he’s been outraged about the incident ever since he saw the video months ago with the rest of the city council.

“There’s underlying problems in our town that we’re not admitting,” he said. “There’s a true desire that people have — they want to address these problems and actually solve them. But we don’t want to necessarily admit that we have these problems.”

Other cities are also grappling with issues of race and policing. The release of the video comes amid an ongoing national debate about whether officers are too quick to use force, especially against minorities. In 2015, the year of Crosby’s encounter, 991 people were shot dead by police in the United States. Last year, 963 were killed.

In Evanston, police say the officers who tackled Crosby were “in compliance with our procedures as it pertains to this type of situation,” according to Sgt. Dennis Leaks, who speaks before the video.

Leaks said the department has refined its policies: “We will no longer require subjects to be prone during these types of stops, as we acknowledge and realize that there are some problematic issues that come with that: locations of the stop, weather conditions and it gives a bad perception.”

Miller said he hopes the black eye this incident has given his city motivates Evanston police to change their training and discipline policies.

“There’s a huge outrage over this in the community already,” Miller said. “And I’m glad that it wasn’t worse, because it could have been.”

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