By CBSBoston.com Staff

DEDHAM (CBS) – A jury found Matthew Potter guilty Tuesday on two counts of involuntary manslaughter in the case of a 2019 bar fight in Quincy that killed Christopher McCallum, a father of three. Potter was found not guilty on three assault charges.

Potter was sentenced to 3-4 years in state prison following his conviction. Potter’s defense attorney had asked for no more than two years.

Prosecutors said McCallum was trying to break up a fight in the parking lot of the Quincy American Legion hall in 2019 when Potter attacked him.

Potter was accused of hitting McCallum so hard he fell to the ground and suffered a brain injury that ultimately took his life.

The jury began deliberating on Monday and reached a verdict one day later.

Christopher McCallum and his wife Kathy. (Family Photo)

McCallum was a 44-year-old father who lived in Bridgewater with his family. He had gone to the bar at the American Legion Nickerson Post on Moon Island Road in January 2019 with his brother to see a band perform that night.

McCallum’s family said he was punched in the face as he tried to break up a fight on the way out, was knocked down, hitting his head. He was pronounced dead the next day.

Before the judge issued his sentence, McCallum’s friends and family offered emotional statements to the court. Among those to speak was McCallum’s son and his wife, Kathy.

Watch: Victim Impact Statements

“He loved his life. He didn’t deserve to have it taken from him. We are all still in shock that he is gone … I had to hold my son while he watched his father take his last breath,” Kathy McCallum said. “How could something so senseless and so violent take the most gentle man that anyone would have ever known?”

Matthew Potter in Dedham Superior Court, Nov. 7, 2019. (WBZ-TV)

A friend of McCallum’s called Potter’s actions “catastrophic.”

“When you took Chris from us, you not only killed Chris, you ruined our lives,” the man said. “I hope your life is a living hell.”

Potter did not take the stand before the judge issued his sentence. Potter’s attorney described his client as having been caught up in a “chaos tornado” the night McCallum died.

The defense argued during trial that Potter was in fact the victim in this case.

Matthew’s brother, Steven Potter, was charged with assault following the incident. The brothers are sons of a retired Quincy police officer.

CBSBoston.com Staff