In dismissing an appeal by the officer, the Appeal Court sided with a lower court decision that upheld an Ontario Human Rights Tribunal finding of discrimination.
Evidence was that the letter carrier, Ronald Phipps, was dressed in a Canada Post uniform and was carrying a Canada Post satchel as he delivered mail door-to-door.
At the time, Const. Michael Shaw, who was on patrol in the neighbourhood, was on the lookout for white men in a vehicle who were suspected of cutting telephone lines.
Even though Phipps did not match that description, Shaw suspected the carrier might have been wearing a postal uniform as a ruse.
The officer claimed his suspicions had nothing to do with the fact that Phipps was a black man.
According to court documents, the officer stopped and questioned the mailman, ran his name through a police check, and talked to a homeowner and a white letter carrier in the area seeking more information about Phipps.
The officer found nothing adverse and Phipps was allowed to continue his deliveries.
In June 2009, the rights tribunal concluded that Phipps had established discrimination in that his skin colour was probably the "predominant factor" in Shaw's actions.
The rights adjudicator also decided Shaw had not offered a credible explanation for his actions to refute the discrimination claim and that police cannot attempt to fight crime based on racial factors.
In a split decision in October, Divisional Court backed the adjudicator, calling her finding reasonable.
Shaw, along with chief of police Bill Blair, appealed to the province's top court.
They argued the adjudicator failed to give enough weight to Shaw's evidence and to the "legitimate role and duty of the police to investigate circumstances of possible wrongdoing."
In its ruling, the Appeal Court noted Shaw stopped and questioned Phipps even though his appearance did not match the white, eastern European men driving a vehicle he had been directed to watch out for.
Nor did Shaw approach or question any white service or construction workers in the same neighbourhood, and he approached a white letter carrier to inquire about Phipps.
Ultimately, the court agreed with the tribunal that Shaw's actions were motivated by race in that Phipps was an unknown black man in an affluent neighbourhood and therefore, he might have been disguised as a postal worker for a potentially criminal purpose.