Arnold Sanderson pleaded guilty Friday to deliberately using his car to run down and kill former work colleague Shawn Smith as he was walking down a road in Charlottetown in May 2006.
Smith was hit by a vehicle and killed as he was walking along the Lower Malpeque Road.
Sanderson was ordered to stand trial in February after a judge found him fit to face the second-degree murder charge following a psychiatric assessment.
Police said Smith was struck from behind when a car swerved across the road and onto the sidewalk.
They ruled out mechanical problems and weather conditions as causes of the incident, and charged Sanderson in November.
The week before the murder charge was laid, Sanderson was charged with making death threats against Smith, who was a former colleague. The two worked together at the former Perfection Foods in Charlottetown 20 years ago.No motive has been suggested for the crime.
Sanderson will return to court Wednesday for sentencing. The mandatory penalty for second-degree murder is life in prison with no chance of parole for 10 to 25 years.