After a longwinded and meandering speech, which included a few funny barbs, May ended with a shout-out to Omar Khadr, who was freed on bail in Edmonton last week.
"Omar Khadr, you've got more class than the whole f****** cabinet," May said, referring to the Conservative party, as Conservative MP and transport minister Lisa Raitt tried to usher her off the stage.
Here's how the Ottawa Citizen's national affairs reporter, Glen McGregor, summed up the moment on the CBC's Sunday Scrum.
"Lisa Raitt ... is basically shooing [May] off the stage because at that point it had gone on so long and had become so uncomfortable, and completely contrary to the tone that these things are supposed to have," he said.
"Leaders come out at these dinners and they're supposed to be self-deprecating and funny, and they'll rib the other leaders but it's all kind of in a good-humoured way. She didn't do that. ... It just went off the rails really quickly and it did change the mood."