The fallout from his sudden disavowal of the long-gun registry has required the front-running candidate to deal with a controversial policy debate just days after the flareup over unflattering remarks he once made about Alberta.
Trudeau handled it Monday by trying to appeal to both sides.
He spent a news scrum with reporters juggling questions on an issue that resurfaced over the weekend with his description of the Liberals' registry as a failed policy.
Trudeau explained that he hadn't actually flip-flopped on the gun registry. In fact, he said, he always supported it, and still does support it in principle. But he said that now that it's gone it's too divisive to try bringing back.
In the next breath, however, Trudeau added that he supports Quebec's effort to bring it back in that province because he said the measure is not controversial there.
Finally, he offered his explanation of how the long-gun registry fits into his definition of a "failed" public policy.
"I voted to keep the firearms registry a few months ago and if we had a vote tomorrow I would vote once again to keep the long-gun registry," Trudeau told reporters.
"However, the definition of a failed public policy is the fact that the long-gun registry is no more... The fact is, because it was so deeply divisive for far too many people, it no longer exists." He repeated that definition of public policy, in both English and French.
Trudeau said he would rather spend the next three years, before the federal election, trying to find evidence-based policies that will unite Canadians and not divide them.
He made the remarks while touring a mall in St-Jean-sur-Richelieu, Que. Trudeau exchanged greetings with several dozen people as he went into shops.
A Quebec reporter asked Trudeau about that province's legal fight to keep its portion of the registry and he replied: "I find it's a very good idea. Because in Quebec it was not at all as divisive as it was elsewhere in the country," Trudeau said.
"Perhaps a solution is to let provinces find different solutions. What's important is protecting Quebecers from gun violence."
The performance earned him a scathing rebuttal from a prominent gun-control advocate.
A survivor of the Montreal polytechnique massacre, which occurred 23 years ago this week, Heidi Rathjen pushed for the creation of the federal registry. On Monday she blasted not only Trudeau's gun policy but also his broader approach to leadership.
"It's just political garbage," she said of Trudeau's policy.
"He's basically saying that the registry is a good thing only where it's popular, but that's not what a political leader does, that's not how you lead — by implementing a public safety measure only where there's no controversy...
"It's not clear, it's confusing and I think it's a cop-out because he wants to please everybody and then he ends up pleasing nobody."
Meanwhile, Trudeau was drawing criticism Monday from people inside and outside his political party.
Another Liberal leadership candidate, Joyce Murray, called Trudeau's initial remarks "disturbing," particularly with the Dec. 6 Polytechnique anniversary looming. She told the CBC that she has always been a strong registry supporter and said she was glad Trudeau had clarified his remarks Monday.
Trudeau was also criticized by an activist former Liberal minister of justice.
Martin Cauchon, who is still pondering whether to run for the leadership himself, told The Canadian Press that leadership contenders need to show they'll stand up for Liberal principles and values.
And he said the controversial registry, created by the government of Jean Chretien in which Cauchon served, is an important part of the party's legacy.
"I believe that we have to update our policies and make sure that next election we're going to be able to show leadership to Canadians," Cauchon said in an interview. "But, you know what, I believe as well ... that a candidate running should have the backbone to respect and stand for the principles that we have always stood for."
Cauchon said party renewal shouldn't mean Liberals have to turn their back on accomplishments such as the Charter of Rights, official bilingualism or even the gun registry.
But Trudeau's position appeared to be seconded by a prominent leadership rival.
Fellow Montreal MP Marc Garneau, thought to be Trudeau's primary challenger, essentially agreed with the front-runner, athough he weighed his words carefully.
"The long gun registry had a lot of very good points and some bad points. On the good side, it was supported by the great majority of police associations in the country, by the RCMP, by victims groups and many others. On the other side of the coin, it was opposed by many Canadians in rural communities in this country. There's no question about it, it was an extremely divisive issue," he said in Ottawa.
"It's gone now. The Conservatives have killed it. Let's move on to other things. It is not my intention to spend more money to bring it back."
Trudeau also received some pushback for stating over the weekend that gun ownership is a key part of Canada's culture.
Garneau declined to criticize Trudeau directly for saying the registry was a failure or for describing gun ownership as part of Canada's culture, other than to say: "I would not have characterized it that way."
The NDP's Nathan Cullen, who represents a rural B.C. riding and opposed the registry, said the comments smacked of insincerity. He said it was a strange position to take for someone who had been a passionate defender of the registry.
"As somebody who represents and lives in rural Canada, it seems to reduce us down to people who simply own guns," Cullen said.
"This is not who we are. We are many things. And people can smell pandering when they see it. Canadians can tolerate quite a bit from their political leaders. Hypocrisy is, generally speaking, not one of those things."
Cauchon also blasted Trudeau for the guns-as-culture comment.
"The point is pretty simple. We're not living in the (United) States," where Americans have a constitutional right to bear arms, Cauchon said. "We're building a different society."
The NDP, meanwhile, still promises to introduce a long-gun measure if elected.
NDP Leader Tom Mulcair, whose own party has been split on the issue in the past, reiterated that a New Democrat government would recreate a gun registry — with some improvements to mollify gun owners, such as decriminalizing failure to register.
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