BOSTON -- The retrial of Alexander Pring-Wilson, convicted of manslaughter in the stabbing death of Michael Colono in 2003, continued on Thursday.

NewsCenter 5's Amalia Barreda reported that the former Harvard graduate student's 2004 conviction was reversed because the defense should have been able to present evidence of the victim's violent past.

"He said to him, he said, 'Did you say something?' Michael said, 'Yeah. Why, you want to do something about it?'" prosecution witness Giselle Abreu said.

That was Pring-Wilson's question that led to a fight and Colono's death April 12, 2003.

"Michael got out of the car and they began fighting," Abreu said.

Abreu was with Colono and her boyfriend that night. She told the jury they parked outside a Cambridge pizza shop and saw a stumbling, drunk Pring-Wilson walk by. She testified Colono ridiculed him. Pring-Wilson approached the car, opened the door and Colono was on him.

"I saw punches swinging left and right," Abreu said.

"And who was punching?" prosecutor Adrienne Lynch asked

"I don't remember. It was both of them pretty much," Abreu said.

When it was over, Abreu described a frantic drive to find a hospital when they realized Colono was bleeding from stab wounds.

She was a cooperative witness who turned surly and hostile when defense attorney Peter Parker pushed her to explain Pring-Wilson's demeanor when he first spoke to Colono.

"Can you say it again? The way he said it?" Parker said.

"'Excuse me did you say something?'" Abreu said.

"With an attitude?" Parker asked.

"Yes," Abreu said.

"With that inflection that you just used?" Parker asked.

"No. That's my attitude," Abreu said.

Abreu's anger led to tears and other testy exchanges when she denied using cocaine earlier that night, admitted they were drinking in the car, and that she told police they didn't know anything about the fight.