A Montreal bagpiper is shocked that he was stopped by police and fined for carrying a ceremonial knife.

Jeff McCarthy played the bagpipes on Wednesday at McGill University's fall convocation ceremony.

He spent the lunch hour at Quartier des Spectacles, wearing traditional Scottish garb and carrying his bagpipes, but when he returned to Place des Arts, he was stopped by three police officers.

One of them questioned him about the hilt protruding from his sock: a sgian-dubh.

"She asked me 'is that a knife?' I said what in my sock? Absolutely," said McCarthy.

The sgian-dubh is a small knife that is part of traditional Scottish Highland dress that includes a kilt and sporran.

"It's an optional accoutrement to be worn in full Highland regalia... it's basically something that goes in your sock, it sits there, and never comes out. I've been carrying one for 27 years and it's always remained in my sock," said McCarthy.

The knife is used for cutting meat or cheese, and guests would traditionally tuck the knife into a sock specifically so that it would be seen by their hosts and not be viewed as a concealed weapon.

Police thought otherwise, and fined McCarthy $220 for carrying a weapon in a public place.

They confiscated the knife as well.

"She advised me that what I was doing was illegal," said McCarthy.

"I tried to explain that this was part of our normal wear... and that I'm normally wearing one when I'm piping."

McCarthy said he understands that laws exist to protect the public, but said the sgian-dubh is, like the kirpan, a now-inoffensive symbol of a warrior tradition.

"The sgian-dubh is not intended to be a weapon whatsoever. It's intended to be an expression of Scottish culture," said McCarthy.

"It's sort of a symbol... and the city is removing symbols or crushing symbols."

Montreal police would not comment on the ticket.