The accused is now 18, but was a minor at the time of Hyatt's death and so she and several other witnesses at the trial cannot be named.
Hyatt was killed at a house party on June 2, 2010 at about 9:30 p.m. PT, said RCMP. The party was hosted by a friend whose mother was away.
Jackie and Clive Sutherland, two of the mother's friends, testified they went to check in on the daughter, and arrived to find a party getting out of hand.
Jackie Sutherland testified she saw teens drunk on the balcony and two boys fighting.
She said she witnessed the accused and Hyatt pushing each other, yelling at each other and heard Hyatt call the other girl a "skank" and a "ho."
Adults tried to break up party before stabbing
The Sutherlands said they told everyone to get out, and the teens spilled out into the yard and onto the street.
Clive Sutherland testified he turned to go to his car and that's when he heard one of the party-goers scream "Drop the knife!" and "You stabbed my friend!"
He told the court he looked to see two teens struggling, one of them trying to take the knife away from the other.
Sutherland said he intervened, grabbed the knife and put it in his pocket, but that in the rush, didn't see who was involved in the fight or who he took the knife from.
He testified he then saw Hyatt on the ground, pale and bleeding from the neck. Hyatt later died in hospital.
Hyatt died from loss of blood, collapsed lung
Pathologists testified Hyatt bled to death from a knife wound to her upper chest. The knife severed an artery on the right side of her neck, above her collarbone.
"It was five centimetres in depth. The tip of the knife, after cutting through the artery also perforated the top of the lung, the right lobe of the lung and caused it to collapse," said Dr. William Currie, who performed the autopsy.
Currie said Hyatt also had cuts to her cheek, earlobe and hairline at the back of her neck, all from one single swipe of a knife.
Forensic experts testified that they found multiple samples on the knife.
That included DNA from a boy who was at the party, the victim Ashlee Hyatt, as well as two samples they were unable to identify because there wasn't enough DNA material to make a match.
Taped testimony played after key witness dies
The Crown's key witness was Hyatt's boyfriend at the time, Mike Baxter, who was killed in a car accident on Oct. 19 — a week before the trial began.
His testimony, recorded at the preliminary hearing, was played for the jury instead.
Baxter testified he had witnessed an earlier argument between Hyatt and the accused over whether or not the accused kissed and was flirting with another boy at the party — who was not her boyfriend at the time.
He said the fight continued out on to the street, where the two began punching each other.
Baxter told the court the accused suddenly had a knife in her hand and was yelling "I'll stab her" at Baxter, at the accused's boyfriend, and at Hyatt.
He said Hyatt fought again with the girl, then stopped suddenly and turned towards him. He said he could see blood gushing from a wound, before she fell to the ground.
None of the Crown witnesses, including Baxter, actually saw the accused stab Hyatt, but the teen was seen holding the knife during the scuffle with the victim and after Hyatt was stabbed, the court was told.
The Crown closed its case on Friday, and defence lawyers announced her client would take the stand on Tuesday.