Accused Vic killer said friend fired gun

A Melbourne man accused of murdering his house mate told his partner his friend fired the gun, a court has heard.

Melton South men Steve Domotor, 49, and Daniel Darrington, 38, are charged with murder over the shooting death of Rocky Matskassy, who lived with Domotor.

Domotor's partner, Maureen Renwick, said when she picked him up after the shooting on March 21, Domotor said Darrington was the one who shot Mr Matskassy.

"He said `Dan shot Rocky in the head'. He just kept saying it," Ms Renwick told the Melbourne Magistrates Court on Tuesday.

The court earlier heard Domotor had made two threats against Matskassy amid months of "whingeing" that he wasn't paying his rent.

Witness Mikaela Reedyk told the committal hearing that on one of those occasions she heard Domotor say, "I'll f***in' knock you c***".

She said Domotor had mumbled the threat to himself, but she knew he was directing it at the house mate.

Domotor's mother, Jennifer Domotor, said she believed her son when he said he didn't do it because he had never lied to her before.

Domotor turned up at his mother's house about 2am on March 22 crying and saying somebody was hurt at his house but he didn't do it, Ms Domotor told the court.

She said she was surprised to see her son at that hour, and he was visibly upset.

"He told me straight away that it wasn't him that did it," Ms Domotor told the court.

"I've never known my son to lie to me. Ever."

Ms Domotor said her son had been on the way to the police station but had decided to "come to mum" first.

"Steve always comes to his mum when he's got a problem," she told the court.

Ms Reedyk said Domotor had wanted to evict his house mate about the time the murder occurred.

"He was saying he wanted him out of the house," she told the court.

The committal hearing continues.