A day after taking a jackhammer to a concrete base for a planned Canada Post community mailbox, Montreal Mayor Denis Coderre says he’s not worried about any legal repercussions.

But one municipal law expert says Coderre may have entered a legal grey area when he drilled into the concrete slab in front of television cameras.

Coderre told reporters Thursday that he did it to send a message to Canada Post, calling the Crown corporation "arrogant" for installing a base for community mailboxes at the entrance to a Montreal nature park without consulting local authorities.

But as a Crown corporation, Canada Post can put its installations wherever it wants on public property, according to the regulations that govern it. And no one is permitted to relocate or remove any Canada Post receptacle or device without permission.

If the concrete slab Coderre chipped away at is “considered a postal installation … he could be in trouble,” said municipal law expert Louis Beauregard.

“But he did not destroy a community mailbox, just the slab,” Beauregard added.

Coderre says he isn’t worried and has no regrets.

“Clearly, I think that I didn’t cross the line that much,” he said Friday.

“I think that I’ve done what I’ve done and was okay to do it … It's not like I tried the devil here. I made a very conscious statement and I felt that it was also a matter of principle.”

Canada Post would not answer questions about what it plans to do next. It just reiterated that it's willing to discuss with municipalities possible solutions and locations for community boxes.

Canada Post's controversial decision to phase out door-to-door delivery and install community mailboxes across the country is expected to save the corporation about $500 million per year.

The NDP has vowed to reverse the cuts. The Liberals have promised a moratorium on any cuts at Canada Post while the issue is studied.

With a report from CTV Montreal’s Tania Krywiak