The lawyer for a Calgary man accused of killing his mother says his client should be acquitted because he was grossly intoxicated at the time.

54-year-old Greg Hetrick was charged with second degree murder after his 79-year-old mother was found dead in her northwest home in March of 2007.

His lawyer says Hetrick should be found guilty of the lesser charge of manslaughter because he claims Hetrick didn't have the capacity to form the intent to kill.

Prosecutors say Hetrick's detailed statement to police shows he knew exactly what he was doing when he allegedly strangled his mother and then stabbed her to make sure she was dead after she refused to give him money for more booze.

The judge in the case has reserved her decision.