17-year-old Matt McKay was killed by Marko Miljevic, then 19, who struck him in the head with a pickaxe in 2007. (CBC) ((CBC))

The Supreme Court of Canada was hearing arguments Friday that a Calgary man's murder conviction for killing a teenager with a pickaxe three years ago should be struck down.

Marko Miljevic, then 19, was high on cocaine and drunk on Sept. 29, 2007, when he hit 17-year-old Matt McKay in the head with the axe after an argument at a garage party in southeast Calgary .

In December 2008, Miljevic was convicted of second-degree murder.

He appealed the verdict, arguing that Court of Queen's Bench Justice Earl Wilson failed to fully answer a question from the jury on the difference between manslaughter and second-degree murder.

In April, the Alberta Court of Appeal ruled that the conviction stands, noting that trial judges routinely decline to give substantive answers to such questions.

Miljevic appealed that decision to the country's top court in Ottawa, where justices began hearing the matter on Friday.


Matt McKay died after he was hit in the head with a pickaxe at a party in a southeast Calgary garage on Sept. 29, 2007. ((CBC))

"The question is whether he should be convicted of manslaughter or murder was really the issue the jury had to determine. And our issue here was that the definition of manslaughter was not properly given to the jury," said Miljevic's lawyer, Noel O'Brian.

According to Evan Osiowy — who had planned to go to the party that night, but stayed away when he heard rumours it had gotten out of hand — Miljevic deserved to be convicted of second-degree murder.

"And then in the morning I woke up to multiple texts saying that yeah, it was Matt McKay that it happened to," said Osiowy, who added that he misses his friend and hockey teammate.

"Fun kid, very funny, always outgoing, always had a smile on his face and could keep everyone smiling."