The Alberta doctor who performed the autopsy on a man who died outside the Hay River, N.W.T., Legion in 2010 testified Thursday in Mark Glen Larsen’s trial for manslaughter.

Brent Nixon, a 50-year-old railway engineer, died after being punched by Larsen outside the Legion bar in August 2010.

Dr. Bernard Bannach said Nixon's blood alcohol was just over three times the legal limit for driving.

He said that slowed Nixon's reactions and relaxed his muscles which caused his head to rotate more suddenly and further when the punch landed.

That caused an artery in his upper neck to tear.

Bannach said the punch would not have killed Nixon if he had been sober.

Larsen himself is scheduled to start testifying at the trial on Monday.