The veteran officer said he was on a walk with his wife at Nose Hill Park when they were approached by two "aggressive" men.
?They said to me: ?Hey, have you been to the Stampede yet?? And my wife and I both looked at him, and we ignored that first comment,? Wawra said.
?They moved a little closer and they said a little louder: ?Hey! Have you been to the Stampede yet?? I believe I said in response: ?Gentlemen, I don?t have need to talk to you about anything. Goodbye.??
The man said he felt uncomfortable without his off-duty hand gun, and wrote that "in Canada, only the criminals and the police carry handguns."
On Twitter, the letter was the butt of jokes. It even spawned its own hash tag: #NoseHillGentlemen.
He said despite all the negative attention his letter has received ? including at least one threatening phone call to his home ? he doesn't regret writing it.
?What concerned me is two young men just approached us and stopped us, stopping us by being in our path, and [began] talking to us without even being welcome to talk to us. They just took it upon themselves to yell at us.?
He said he should have the right to protect himself if things had escalated.
With files from the CBC's Mary-Catherine McIntosh