The family of Daniel Haworth says he suffered brain damage after a violent arrest that led to charges against a Calgary police officer.

Haworth’s brother said that even though he was a drug addict, he didn’t deserve the treatment he got the day he was arrested on May 25, 2015.

Surveillance video showed Haworth being taken from a police car in handcuffs after being arrested for breaking into his ex-girlfriend’s home. In the video, the officer appears to punch him from behind three times before throwing him to the pavement.

“I was shocked,” said his brother Robert Haworth. “I had this picture in my mind of the event from the way Danny had described it already which was much tamer than the actual assault itself so when I saw what actually happened I was shocked, I couldn't believe someone in a position of power and trust would attack someone that ferociously.”

“It was shocking, it was very hurt, its someone that you love being hurt and it was very difficult to watch,” said Cathy Haworth, Daniel’s sister-in-law.

Haworth was sent to the hospital and diagnosed with permanent brain injury that caused numbness and memory loss.

The officer, whom the family identifies as Constable Trevor Lindsay, is now on paid leave, charged with aggravated assault.

“A rational thinking human being doesn't behave that way, we hope he gets the help he needs, we hope he can stand up and admit he did something wrong, that would be huge for our family,” said Robert.

But Lindsay's lawyers said in a statement, "My client maintains his innocence, intends to advance a vigorous defense and will respond only at the appropriate time and manner in a court of law where all of the evidence will be considered."

Daniel Haworth later died of an unrelated overdose.

Overall, the family says police have been good to them. Their father was an officer, and it was a cop who worked for 20 minutes to keep Daniel alive following the overdose that killed him.