There's a risk his approach could plunge the country into another sprawling round of constitutional wrangling over a host of divisive issues, the Montreal MP acknowledged Friday.
And even if the talks remained focused strictly on the Senate, he allowed it could prove impossible to find provincial agreement on the kinds of reforms that should be undertaken.
Still, in a jab at leadership front-runner Justin Trudeau, Garneau said fear of failure shouldn't deter political leaders from at least trying to turn the appointed Senate into an elected chamber.
"Just because it's a difficult issue doesn't mean there isn't a solution and I think if you approach it in the right way, and it may take some time, you may be able to find that solution," Garneau said in an interview.
"It's better to explore that than to be afraid to explore that."
Garneau said the comprehensive reform he has in mind would include election of senators, term limits, a redistribution of seats to provide more equitable representation for each province and a deadlock breaking mechanism to prevent gridlock between the House of Commons and elected Senate.
Canadians' enthusiasm for reforming or abolishing the chamber has grown recently as various scandals have beset the Senate.
The Senate's reputation has been sullied by allegations that at least three senators — Conservatives Patrick Brazeau and Mike Duffy and Liberal Mac Harb — abused taxpayer-funded housing allowances. Duffy announced Friday he will voluntarily repay his allowance.
Questions have also been raised as to whether Duffy and fellow Conservative Pamela Wallin actually reside in the provinces they were appointed to represent.
Capping a rough few weeks, Conservative Patrick Brazeau was forced earlier this month to take a leave of absence after being charged with assault and sexual assault.
Trudeau has said he'd try to make the existing Senate work better by appointing higher-quality senators, rather than trying to change it.
A key Trudeau ally, New Brunswick MP Dominic LeBlanc, dismissed Garneau's stance on Senate reform as unrealistic.
"It's a fantasy to pretend you're going to get the premiers of Nova Scotia, Prince Edward Island, Manitoba and Newfoundland to agree with the premiers of Ontario and B.C. on Senate reform," LeBlanc said in an interview.
Moreover, he predicted it would be impossible to open negotiations on the Senate without triggering a flood of demands from provinces, aboriginal groups and others to address a host of other constitutional issues and grievances.
"It would be a quagmire that would see no end."
But Garneau argued that Trudeau's stance amounts to settling for the status quo.
"I don't agree with just saying, 'Oh well, we'll just have to more carefully choose our senators next time.' I'm sure that's been said probably, oh, I don't know, 20 times in the course of the history of the Senate, usually when a senator behaves badly," he said.
"But fundamentally, I'm against maintaining a patronage approach to the Senate."
Some provinces favour reforming the Senate while others support outright abolition. Those that support reform do not necessarily agree on how to go about it.
Western provinces are grossly under-represented in the Senate and would doubtless demand equal or more equitable representation in an elected chamber. The Atlantic provinces, which are vastly over-represented, would no doubt resist any diminution in their clout.
Garneau acknowledged it would be a daunting task to find agreement.
"An honest effort can be made and if it doesn't work out, it doesn't work out. It needn't divide us. It can be done in a positive and constructive way."
LeBlanc also went after Garneau for accusing Trudeau of needlessly inflaming Quebec sovereigntists with a suggestion — later clarified — that at least 66 per cent of Quebecers would need to vote for independence before the federal government should negotiate secession.
Trudeau was highlighting the "idiocy" of the NDP's position that a bare majority of 50 per cent plus one vote would be sufficient when it takes a two-thirds majority to change the party's own constitution, LeBlanc said, adding that Trudeau has consistently supported the Clarity Act, which requires an undefined "clear majority."
Whereas Trudeau has been "clear, tough and unequivocal" in lambasting the NDP stance, LeBlanc said, Garneau has been "silent." And he said Garneau seems to be suggesting Trudeau shouldn't talk about the issue in Quebec for fear of angering separatists.
"I hope that Marc doesn't take such a weak-kneed, short-sighted approach."
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