The controversy made global headlines but hasn't led to a drop in the polls for Mr. Trudeau, who has been admired by liberals around the world for his progressive policies in the Trump era Mr. Trudeau has long championed multiculturalism and immigration.
The most frequent battles of the night were between the current prime minister and the current leader of the opposition-and it started off the top.
Regardless of the question, the NDP's Jagmeet Singh took every opportunity to repeat his favourite theme: that Liberals and Conservatives alike pander to wealthy corporations whereas the NDP will fight for ordinary Canadians with investments in child care, pharmacare and dental care. The PM certainly had the biggest platitudes.
While he avoided answering the question in the moment, when questioned about the encounter by the media a few days later, he confirmed his personal views, but committed to keeping the issue left well enough alone.
Trudeau's reticence to be pinned down on Bill C-21 is hardly surprising.
The Bloc Quebecois' Yves-Francois Blanchet has little to gain or lose in front of a national audience primarily of English-speakers.
"The Liberals don't allow you to earn income within a corporation if that income exceeds $50,000 per year".
But the format of the debate and the sheer number of leaders on stage made substantive debate on policies hard and, with leaders talking over one another, often impossible to hear. In the debate later, he suggested Trudeau seek the vacant leadership of the Ontario Liberal party, since he's so interested in provincial issues.
Once again, the prime minister employed the same rope-a-dope tactic with May that he used with the others. She says fact-checking showed that most of what the leaders said about climate change was inaccurate.
'Justin Trudeau only pretends to stand up for Canada, ' Scheer said. Each launched into their responses, but Green Party leader Elizabeth May was the only candidate to begin with a land acknowledgement recognizing that the debate was taking place on the traditional territory of the Algonquin people. The rest of the leaders were encouraged to scuffle with Bernier about controversial comments he has made about immigration in Canada and about teen climate activist Greta Thunberg. "I think you are a Liberal". "Your ideas are hurtful to Canadians". "Harper did, a very different choice than Andrew Scheer is proposing".
"When Andrew Scheer went low early he set the tone for the debate", she said.
The beneficiary of the intra-leader sniping was the prime minister, who knew that every minute they spent arguing with each other was a minute he didn't have to bob and weave.
Scheer is also dealing with thoughts about why he did not expose he has dual US citizenship.
Going into the English language debate, pollsters were painting a familiar picture of the political landscape - a country disengaged, confused, and most importantly undecided.
The Nanos three-day tracking poll showed the Liberals at 34 per cent support and the Conservatives at 33 per cent support, while an Abacus Data poll showed the Liberals at 35 per cent and the Conservatives at 33 per cent. More than once, chaos reigned on stage, with leaders speaking over each other, leading to gibberish.
On a crowded stage where debate often devolved into a cacophony of crosstalk, Canada's federal leaders - including a fringe far-right candidate - have sought to sway voters before the country's election.