Cpl. Benjamin "Monty" Robinson testified Tuesday that he drank five beers before the crash that killed 21-year-old Orion Hutchinson, but felt fit to drive and only left the scene to take his children home.

Robinson, who is charged with obstructing justice in the fatal collision, told the court he downed the beers at a Halloween party over a four-hour period before driving his Jeep into Hutchinson's motorcycle at a Tsawwassen intersection on Oct. 25, 2008.

The off-duty Mountie, who has first aid training, said he left the young biker at the scene because "someone was already there" attending to him.

"I just wanted to get my kids out of there," Robinson said.

Prosecutors say the off-duty Mountie left his licence at the scene, walked home and took two shots of vodka because he knew it would help him avoid impaired driving charges.

But Robinson told the court he was an alcoholic at the time of the crash, a condition that had enflamed following his involvement in the infamous Tasering death of Robert Dziekanski.

Robinson testified that after he got home on the night of the crash, he found himself walking downstairs to his bar without thinking.

"I went for what has given me comfort," Robinson said.

Robinson also refuted the testimony of his former high school classmate, Anne Marie Rough, who told the court Monday that she overheard the officer discussing ways to evade drunk driving charges.

Rough said one method Robinson described was leaving your licence at a crash scene, drinking shots and then coming back so no one could tell when the alcohol entered your system.

The Mountie is currently suspended from the RCMP and is awaiting trial on a perjury charge related to Dziekanski's death.

Robinson testified Tuesday that the Dziekanski incident still causes him to suffer flashbacks, nightmares, night terrors and nausea, and he's currently being treated for post-traumatic stress disorder.

Robinson said he stopped associating with many of his friends after the fatal Taser incident, and began staying home more due to his portrayal in "negative media."

He is scheduled to appear in court on the perjury charge in April 2013.

With files from Maria Weisgarber