A key witness in a Barrie murder trial remained defiant on the stand, despite a warning by the judge that she would be held in contempt of court.

The defence tried to paint its version of events on the night Milan Segoda was killed at a rooming house in 2015. They questioned Amy Novak's presence at the rooming house.

She refused to answer many questions from defence lawyer Anthony Robbins. Novak insisted at least 50 times, "I don’t remember."

"Whatever you have on paper, you have on paper. I don’t remember," Novak said. Robbins replied, “I suggest that you’re trying to put Terry in a bad light."

Novak fired back, "I suggest that you’re trying to put me in a bad light."

Novak's former boyfriend Terrence Barrett is on trial for the murder of Segota, who was stabbed 22 times and killed in the hallway of their Ross Street rooming house.  

Novak has testified she tried to break up the fight between Barrett and Segota, before Segota died in front of her at the hands of Barrett.

As the day went on, Novak refused to cooperate with more of the defence lawyer's questions.  The judge again admonished her and reminded her of the consequences.

"My client is facing some very serious charges," Robbins said.

"That's too bad for him,” Novak said. “He's the one that did it."

Trying to poke holes in her story, Robbins then said, "After Mike fell, you went to your room. I’m suggesting Terry was standing and you grabbed your red knife and went to your room."

"No I did not," said Novak.

"You started yelling ‘I've been stabbed.’"

Novak said, "No I did not. I didn't know I had been stabbed until I went to change my clothes."

Novak is expected to be back on the stand Wednesday morning to face more questions surrounding Segota's death and her presence at the rooming house on that night.