It took just minutes for Lawrence Crosby, a law-abiding African-American PhD student, to be tackled to the ground, punched and cuffed by a swarm of cops in the US before being accused of stealing his own car.

Yet almost two years after that night on October 10, 2015, Evanston Police Department have released dashcam video of his arrest as Mr Crosby pushes a damages case against those same police officers for wrongful arrest and excessive force.

"This is my vehicle sir, I was trying to fix something on the roof," the Northwestern University student can be heard saying from beneath the crushing restraint of the officers in video of his arrest.

"When we tell you to get down, you gotta get down," one of the officers can be heard saying.

To which Mr Crosby replies "yes, sir" before politely enquiring why his hands have been cuffed.

After being told the cuffs are a precaution until the officers can determine whether the car is stolen, Mr Crosby nervously rattles off the make of the car, when he bought it and where he bought it.

This calm insistence appears to placate one of the officers enough for him to slowly step away and call dispatch for the name of the car's owner. The car, the operator confirmed, belonged to a Lawrence Crosby - the same Lawrence Crosby pinned to the ground.

Mr Crosby found himself at the bottom of the unwanted scrum after a concerned citizen driving past thought she saw him stealing a car. She phoned police before stopping and watching the night's events unfold. As it became clear that she had made a mistake, the 911 caller began to sob with regret.

"It looked like he had a bar in his hand… I feel really... I didn't mean to like racial profile… I mean, I don't want to….," she said before the officer interrupted her.

The US police department reluctantly released the 40-minute footage of Mr Crosby's arrest this week after a Freedom of Information request forced their hand. Evanston Police Department sergeant Dennis Leaks offers a statement justifying police action contained in the video.

As well as showing the force used against Mr Crosby, audio of a casual conversation between officers in the aftermath of the incident is recorded.

"He didn't get shot…so he should feel happy about that," one officer can be heard telling another.