Vojneski, 31, is on trial for murdering his girlfriend Paula Conlon, 30, in her Macgregor home in March 2012.

Ms Conlon, a mother of three, was found dead with 11 stab wounds, lying on a single bed in her room.

Her boyfriend, whom she'd met at a psychiatric unit in October 2011, stands accused of the frenzied stabbing attack.

The Crown, represented by prosecutor Shane Drumgold, is currently leading evidence of Vojneski's alleged violent tendencies.

They allege that when Vojneski gets angry, he gets violent, and he has a tendency to use knives.

The fifth day of the ACT Supreme Court trial heard from a prison guard at the Alexander Maconochie Centre.

The guard spoke of an assault that occurred when Vojneski was incarcerated in the facility in August last year.

Inmates at the AMC are allowed to complete "buy ups", where they use their own money, stored in a prisoner trust account, to order groceries, tobacco or toiletries.

Vojneski approached the guard, alleging someone had forged a "buy up" under his name, leaving him out of pocket.

The guard began to investigate, and then told Vojneski to fill out a prisoner complaint form to take it further.

The corrections officer was later outside in an external yard, speaking with another guard, when he heard raised voices coming from inside the nearby cell block.

The guard said he began to walk to the block to investigate, when Vojneski burst out of the door.

"The door burst open and Mr Vojneski came out into the external yard and proceeded to assault me," he told the court.

Vojneski, he said, landed three punches, including one to the bridge of his nose and back of his head.

Another guard came out and helped restrain and handcuff Vojneski, the court heard.

CCTV footage of the incident was shown to the court.

The trial continues before Justice John Burns.