OTTAWA -- A dead man's underage girlfriend lied about seeing his alleged murderer hold a knife to his throat, a defence lawyer charged Monday.

The now-18-year-old woman -- who cannot be named because of a publication ban -- had testified Friday that Toby Land threatened to kill Dominic Doyon, 31, about a month before Doyon ended up dead.

She was the object of that fight, the court has heard -- a 14-year-old girl dating a man twice her age.

Land hadn't approved.

"If you ever date a 14 to 15-year-old again, I'll kill you," she claims Land told Doyon on April 1, 2009.

Doyon was stabbed to death with a sword, and beaten with a hammer and crutches late on May 4, 2009.

Land is on trial for second-degree murder.

Defence lawyer Neil Weinstein picked apart the woman's testimony during cross-examination.

She had told the cops that Doyon and Land had a huge screaming match in the kitchen of Doyon's filthy apartment.

"They were actually just screaming," she told police in May 7, 2009, statement. "It's like, 'Oh, you're a fool,' blah blah blah, 'Why are you hanging out with little kids?' and all that kind of stuff.

"I hate when they're screaming and that, so I said I'll just leave."

But on Monday, testifying through an interpreter, the woman said the two men were whispering.

"Do you see that whispering and screaming are opposites?" Weinstein asked. "They can't both be true, can they?"

The woman insisted that she meant to say "whispering." I didn't know how to say whispering in English," she said.

So the men's whispering was what drove her to leave, Weinstein asked in disbelief.

"You know you're under oath, right?"

The woman smirked, but clung to her tale.

She had also spent all morning telling the jury that it had just been she, Land, Doyon and possibly their roommate in the flat when the confrontation took place.

But when Weinstein reminded her of her preliminary hearing testimony, the woman suddenly recalled two unnamed native men, who were in the apartment with them.

Although they were friends with Doyon and were -- in one version of the woman's tale -- inside the small apartment when Land threatened Doyon, they did not intervene, the woman said.

The trial continues.