Conflicting stories as day-one of testimony began in the murder trial of a Westside man.

The victim was 34-year-old Robert Blake Isaac. The accused was the victim's roommate -- 32-year-old Cameron Louis Simpson.

The Crown contends that Simpson killed Isaac two years ago in their West Kelowna home following an argument.

The argument was over a party. The Crown says Simpson invited a couple of friends over, but Isaac took exception seeing that he was using the living room as his bedroom.

The two got into an argument resulting in Isaac being stabbed. But how the stabbing occurred is not clear.

According to the Crown, Simpson called 9-1-1 stating that Isaac came after him with a knife. He took it from him and that's when Isaac was stabbed. However, Simpson later told police that he pushed Isaac, causing the victim's arm to swing around before the blade penetrated Isaac's chest.

The Crown alleges that Simpson left the scene of the crime only to return a short time later.

He's charged with second degree murder.