After stabbing a fellow partygoer in the neck with a chisel, a 17-year-old boy told police he hoped Levi Marance would die, according to the facts read aloud after the teen pleaded guilty to manslaughter in a Calgary courtroom on Monday.

The young man's identity is protected by a publication ban under the Youth Criminal Justice Act.

"Hopefully that person died, s**t," TT said to police. "Pretty funny."

TT's attitude changed after he slept and sobered up at Calgary police headquarters, according to an agreed statement of facts read aloud in court.

A group of young people had been drinking and doing drugs at an apartment in the city's northwest in July 2015 when Jessie Copenace became agitated. Marance, 18, and TT thought Copenace might be having a bad trip and brought him into a bedroom to try to calm him down.

Eventually, Marance — who was from Red Deer — and Copenace began fighting, and TT joined in. Between TT and Copenace — who pleaded guilty to manslaughter earlier this year — Marance suffered 35 stab and slash wounds.

When police and paramedics arrived, blood was gushing from Marance's neck. Officers performed CPR but he was pronounced dead shortly after arriving at Foothills hospital.

With the help of their helicopter, police found TT on a nearby street and arrested him. They also found a bloodied shirt he'd thrown in the garbage that testing would eventually show matched Marance's DNA.

Levi Marance, 18, was killed with a chisel during a party at this northwest apartment building. (Kate Adach/CBC)

Right after the arrest, police found TT was too intoxicated and "belligerent" to interview, so they gave him food and a mattress and let him sleep.

Afterward, TT stopped laughing about Marance's death and admitted to stabbing the victim at least twice, including once in the neck.

Originally charged with second-degree murder, Court of Queen's Bench Justice Charlene Anderson accepted a guilty plea to the lesser offence of manslaughter.

"That's terribly tragic," said Anderson after hearing the facts of the case.

Defence lawyer Kim Ross says his client's guilty plea should be seen as an expression of remorse.

"He's extremely remorseful for what happened. He obviously wishes this event would never have occurred, but he is stepping up and accepting responsibility," said Ross.

Before the hearing got underway Monday morning, Ross showed his client a note written from Marance's mother to TT's mother.

"It was a note from the victim's mom, to my client's mom, and just basically expressed sorrow for what everybody was going through," said Ross.

The sentencing hearing will take place in January.