09/13/2011 06:44 EDT | Updated 11/13/2011 05:12 EST

Langley road rage trial begins in B.C.

The trial of a 41-year-old Langley, B.C., man accused of running down and killing 21-year-old Silas O'Brien — in what some are alleging is a case of road rage — began Monday in New Westminster.

Brent Parent has pleaded not guilty to five charges related to dangerous driving and criminal negligence causing death.

On an early morning in March 2008, O'Brien and two friends were driving to Seattle to catch a flight to Hawaii. O'Brien died on the way.

His family has waited 3½ years to find out why.

Sam Dooley and Luke Stephen were with O'Brien when he died. In court on Monday, the friends recounted the events of that morning.

Dooley and Stephen said the Chevy Silverado they were in was run off the road and into a ditch as the trio tried to pass a Ford F-250 pickup truck that had stopped in front of them on 16th Avenue.

Unharmed, the three young men climbed out of the ditch. The pickup truck had gone, but then came back.

Dooley told the court he was waving and yelling for the truck to stop. When it swerved toward him, he jumped out of the way and then saw it hit his friend.

"I turned at the exact point he made contact. I saw something come out from underneath the wheel. I was yelling for Si saying 'Luke has been hit,'" Dooley said.

"Luke comes out of the ditch and said it was Silas."

Stephen broke down within minutes of taking the stand.

"I saw the truck coming. When I jumped back into the ditch, I looked up and Silas was getting hit," Stephen told the court.

Parent's defence lawyer, Vincent Michaels, said he expects his client will take the stand.

The trial is scheduled to last two weeks.