Lawyers for a pastor who is suing Chicago police for excessive have released dashcam footage of an incident showing the woman being pepper sprayed and beaten by officers during a traffic stop - as at least one cop stands by laughing.

Reverend Catherine Brown says she was 'treated like an animal' and feared for her life during a terrifying encounter with police in May 2013 while her two children - aged eight and one - were in the car.

Brown told CBS Chicago that was pulling into her driveway with her children when she almost hit a squad car without its lights on, which was pulling out of the driveway.

She claims a female officer, Michelle Murphy, got out of the squad car and started yelling, while another officer, Jose Lopez, also approached her.

Dashcam: This is the moment Officer Michelle Murphy sprays pepper spray into the car, hitting Reverend Catherine Brown and her baby, while Officer Jose Lopez (right) stands by watching

Funny, is it?: Officer Lopez is seen laughing in the footage as the mother is hit with pepper spray and screams

In the footage, Catherine Brown (far right) can be seen being dragged across the hood of a parked car by the two officers

'(They) beat me down to my underwear, pulled my skirt off me,' Brown said of the encounter

'I reached for my license ... the other officer takes the gun and points it at the front of my head,' Brown told CBS.

Brown called 911 several times, believing she was being mistreated.

In the tapes, you can hear her eight-year-old and one-year-old daughters crying in the background.

Brown then panicked and quickly reversed back out of the driveway into the street, hoping to find a neighbor that would help her.

The police officers then chased her with their car.

'Now she's chasing me with the car. I come to a complete stop, and then she takes the car and rams it into me,' Brown says.

Scared to death: Reverend Catherine Brown says she was 'treated like an animal' and feared for her life during a terrifying encounter with Chicago police while her two children - aged eight and one - were in the car

CCTV footage taken in the street shows Brown speeding out of her driveway in reverse as she flees the cops

Brown then got out of her car screaming, and Officer Murphy can be seen in the dashcam footage hitting her with pepper spray.

The spray also hit Brown's baby daughter.

In one incredible point in the video, Officer Lopez can be seen laughing.

Officer Murphy then gets on top of the police cruiser and points her gun at Brown, whole Officer Lopez strikes Brown's car with his baton.

Brown was then dragged from her car, over the police cruiser and thrown to the floor.

'(They) beat me down to my underwear, pulled my skirt off me,' Brown said.

'They beat me with the sticks and hit me with their boots in my head.'

'I got treated like an animal.'

Terrified: Brown's eight-year-old daughter was in the car at the time, along with her one-year-old daughter

Brown was charged with attempted murder because Officer Murphy claimed Brown had dragged her, but she was acquitted of the charge.

However she was convicted of reckless conduct for driving in reverse out of the driveway, which she is appealing.

She is also suing for excessive force, seeking unspecified damages.

Chicago police say they aren't able to comment because of the lawsuit, but said they take allegations of excessive force very seriously.