A killer who gunned down a career criminal in an ambush has refused to stand for a judge as he was sentenced to 32 years’ jail time.

Jason Milhuisen, 39, remained seated and stared down Supreme Court Justice Jane Dixon today as she sentenced him for the murder of Daniel O’Shea.

A jury in December found Milhuisen guilty of killing O’Shea, 41, at a South Yarra reserve in Melbourne’s inner southeast.

Witnesses heard gun shots ring out of Fawkner Park about 7.30pm on April 26, 2019, as O’Shea was shot four times, three to his body and one to his head.

Milhuisen claimed he was not the shooter but the jury decided he was the one to fire the bullets, Justice Dixon said.

“This was a grave offence demonstrating a callous disregard for the precious value of human life,” she said in sentencing.

Justice Dixon noted O’Shea had convictions for drug trafficking and was described by prosecutors as a “career criminal”.

She accepted Milhuisen did not have any personal grievances towards O’Shea and the 39-year-old instead acted as a “gun-for-hire” at the behest of another person or group.

“I accept it had all the hallmarks of a planned hit,” Justice Dixon said.

The judge found the attack was brazen as it took place in a public place, although no community members were close at the time of the shooting.

It was also aggravating that Milhuisen discarded two guns in Fawkner Park as he fled the scene, Justice Dixon said.

Justice Dixon accepted Milhuisen had experienced difficult conditions in custody and his continued isolation from his family would make his time in prison more difficult.

But she found he had no remorse for his crimes and his moral culpability was high as she sentenced him to 32 years behind bars.

He will be eligible for parole after 21 years, having already served just over four years of his 25-year non-parole period.

Milhuisen refused to stand as the sentence was handed down and again when the judge left the bench, as is customary in the courtroom.

His barrister Peter Morrissey SC told reporters his client maintained his innocence and was planning to appeal his conviction.