The man convicted of killing Canberra truck driver Bob Knight has laughed after being sentenced to at least five years and nine months in jail.

Mr Knight was shot dead while he was in his truck waiting at traffic lights at Milperra in Sydney's south-west in 2009.

He was hit by a stray bullet from a gunfight between rival family groups in a restaurant carpark.

Canberra man Bob Knight was killed by a stray bullet in 2009. ( AAP: supplied )

Mahmoud Mariam was found guilty of Mr Knight's manslaughter after firing off several shots from his pistol during the fight.

In the NSW Supreme Court today, Mariam was sentenced to a minimum of five years and nine months' jail but will be eligible for release in April 2016.

In sentencing, Justice Megan Latham said the 28-year-old wore his contempt for the law like a badge of honour.

"The offender was a mature adult who consciously and arrogantly engaged in a mindless display of violence in the presence of much younger men," she said.

"The offender himself has at no stage expressed the slightest remorse for the death of Mr Knight."

Mariam laughed as he was escorted out of the court room.

Another man involved in the fight has been sentenced to two years in jail.

Two teenagers convicted of affray for their part in the fight have avoided jail.

They were both been given three-year good-behaviour bonds.

Mr Knight's family welcomed Mariam's sentence, but criticised him for appearing to laugh and joke with his relatives after it was handed down.

"This was not a tragic accident as these criminals would like you all to think," Mr Knight's daughter Cathy said.

"These people set out, with guns blazing, to blow each other away.

"Stupid idiots couldn't even get that right... the wrong person died."

NSW Premier Barry O'Farrell has slammed the penalty given to Mr Knight's killer and says he has asked Attorney-General Greg Smith to investigate whether it can be toughened.

"That decision is clearly inadequate," he said.

"It's the sort of decision that lowers community confidence in the judiciary and it's one that I've asked the Attorney-General to provide a report to me as to what if anything can be done to ensure that what should be a tougher penalty is imposed."