The Liberal leader said Wednesday that details of his economic policies will have to wait until the party unveils its platform for the 2015 election.
He was not so averse, however, to repeating his confession that he smoked marijuana after becoming an MP — an issue he's using to portray himself as more transparent and honest than traditional political leaders.
"I admitted that a few times in my past I partook of marijuana," Trudeau told a huge crowd of adoring partisans at an evening rally at the Prince Edward Island farm of Liberal MP Lawrence MacAulay.
"That sounds so formal. I took a puff on a joint a few times as a younger person. Now, the issue is what became of that was a huge debate in political circles that blew my mind.
"I mean, only in (Prime Minister) Stephen Harper's Canada could people actually argue that being honest is a calculated risk."
The rally, which attracted what appeared to be more than 1,000 supporters, capped a day in which Trudeau and his caucus discussed their two priorities for the fall: transparency and the economic challenges facing middle-class families.
But while he was happy to talk about openness, Trudeau was far less forthcoming when asked for details of his economic plan.
"This is not something to take lightly," he said during a mid-day break in the Liberal caucus retreat.
"It's not something to reel off because people want answers. People want answers — but people want to be part of generating those answers.
"And that's where the Liberal party is absolutely serious about the kinds of meaningful consultation and working with Canadians to build a platform that reflects both the priorities, concerns and solutions that Canadians are generating across the country."
Trudeau made improving the lot of the middle class the central pillar of his leadership campaign and has continued that theme since becoming leader in April. But while he and other Liberals frequently rattle off statistics demonstrating that middle-class families struggle to make ends meet, he has yet to spell out what he'd do to help them.
During the leadership race, Trudeau similarly argued that platform development should be a bottom-up exercise, not something handed down from on high. His rivals complained he was offering nothing but vague platitudes but their criticism found little traction among party rank and file, who elected Trudeau by a landslide.
Trudeau's severest critic was erstwhile leadership rival and fellow Montreal MP Marc Garneau, who is now a convert to the wait-and-see approach.
"Guess what? I lost. He won. He's a smart guy and I'm totally behind him on that," Garneau said in an interview Wednesday.
While some people want to see a leader offer detailed policy, Garneau said he's concluded that voters are looking more broadly for "a whole bunch of things" in a leader, including personality, character and general "messaging" that appeals to them.
Whether Trudeau's approach will work with voters in general remains to be seen. But pressed repeatedly Wednesday by reporters to finally put some meat on the bare bones of his pledge to improve the lot of the middle class, Trudeau didn't budge.
"My responsibility is to put forward a comprehensive, robust platform in 2015 that is going to demonstrate to Canadians that the Liberal party is serious about working hard for them and responding to their concerns. And I'm not going to short-cut that process, which is a serious and responsible process, just because people want to know right now and they're impatient to know."
Liberal MPs and senators will begin the consultation process in earnest on Sept. 16, returning to Parliament as originally scheduled, even though Harper has announced his intention to prorogue and begin a new sitting some time in mid-to-late October.
They'll hold roundtable discussions and meet stakeholders on various issues, Trudeau said, filling the void left by Harper's delay in recalling Parliament.
Earlier Wednesday, Trudeau, presiding over his first annual summer caucus retreat, kicked off proceedings with an upbeat message to Liberal MPs and senators.
"There's a lot of reasons to be optimistic. People are excited about the change we represent and the new way of doing politics we're bringing forward."
That said, Trudeau warned there's still "an awful lot of hard work" ahead to bring the party back into contention by the next election, after it was reduced to a third-party rump in 2011.
"It's back to school across the country and I am a former school teacher," he joked as he instructed MPs and senators to pick up their pens and, for the sake of the TV cameras briefly allowed into the room, to at least pretend that they're "hanging off of my every word."
Some of the heaviest lifting the Liberals must do involves fundraising.
Long the party most reliant on large donations from corporations and wealthy individuals, the Liberals still have not fully adapted to political financing reforms introduced in 2004, which severely restricted individual donations and banned corporate contributions altogether.
Liberal fundraising lags well behind the Conservative money machine, which excels at prying small amounts of money out of thousands of donors.
The Trudeau team announced Wednesday that it has engaged a fundraising heavyweight — Stephen Bronfman — in a bid to become more competitive with the Tories. Bronfman, a longtime Trudeau friend and scion of one of Canada's wealthiest families, was in charge of fundraising during Trudeau's leadership campaign, producing an eye-popping $2 million.
Since Trudeau became leader in April, the Liberals have vaulted into first place in opinion polls, a status that has not so far been dented by last week's admission that he smoked marijuana after becoming an MP.
In keeping with the transparency theme, Liberal MPs and senators were presented Wednesday with a template for posting quarterly travel and hospitality expenses online. Trudeau, who promised greater transparency last spring amid the uproar over the Senate expenses scandal, said the new postings will begin Sept. 16.
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