Already, the NDP is signalling that it likely won't support all or any of the new provisions in the Parliament of Canada Act, which originated in a Private Member's Bill by Conservative MP Michael Chong.
The Liberals are only just beginning to consider the implications. One high level source suggested many inside the party don't see the need to bind themselves by the provisions.
NDP House Leader Peter Julian refers to Chong's bill, passed into law in June, as the "Conservative Reform Act."
When he put forward the bill, Chong said it was designed to rebalance power between MPs and the party leaders. The four changes that each caucus will need to vote on before they get to anything else are:
— Whether MPs have the power to trigger a secret ballot leadership review after 20 per cent of them request one.
— Whether MPs have the power to suspend and reinstate colleagues via secret ballot.
— Whether MPs have the power to elect interim leaders.
— Whether MPs have the power to elect and eject their caucus chairpeople.
Julian said the NDP caucus already elects its own chairperson, and the party members, including MPs, have the power to trigger a leadership review at their conventions. As the longest continuously serving MP, Brian Masse will preside over the first meeting.
"The Reform Act is something that was brought, I think, in the specific circumstance to try to pry open the lack of democracy within the Conservative caucus, but the NDP has already followed those practices and gone beyond those practices for many years," said Julian.
"That's why I say, when we talk about the Reform Act, we're actually talking about the Conservative Reform Act — it seeks to reform the Conservative party practices."
But the NDP's constitution does not match or surpass the new provisions on the question of interim leaders. The party rules hand its governing council the ability to appoint the interim chief, in consultation with the caucus. Nycole Turmel was appointed interim leader in 2011 after an ailing Jack Layton recommended her.
The current provisions also mean that only nine NDP MPs would have to sign a notice requesting a review of Thomas Mulcair's leadership for that secret ballot vote to occur.
The Liberals have not yet communicated a caucus meeting date to MPs — the cabinet is to be sworn in on Wednesday. Prince Edward Island MP Lawrence MacAulay is the dean of the caucus. If he is appointed to cabinet, this could create an unusual situation where he is part of the ministry and presiding over important questions for individual MPs.
The Conservatives are facing the tricky question of whether to exclude senators from their vote for interim leader. The Chong bill specifies that only MPs can participate in the votes while the Conservative constitution refers to the parliamentary caucus.
Conservative Sen. Michael MacDonald points out that the only opposition parliamentarians in Atlantic Canada right now are Conservative senators, since the Liberals won every seat in the region.
"I think it's fair that we see ourselves as the elders of the party, particularly in a time of transition, and a lot of balls are in the air, a lot of uncertainty," said MacDonald.
"I don't think it's out of the ordinary for senators to be involved in decision making at a time when there's a vacuum. We are a party with a constitution that calls for this, and also because the provisions of the Reform Act aren't set in stone, they have to be triggered by votes."
The MPs have a competitive interim leadership race on their hands, with eight candidates in the running (including two running as a team).
Former MP James Rajotte says the contest is a chance for the caucus and the party to choose how it wants to define and present itself going into the formal leadership
"For most people in that caucus, the only leader they have ever known is Stephen Harper, and now they have an opportunity to choose the interim - the first decision is a big decision."
—With files from Stephanie Levitz.
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