MONTREAL - Future votes on Quebec's independence could be triggered by popular demand, if the Parti Quebecois is elected to government.

The provincial opposition party adopted a policy Sunday to introduce citizen-led referendums in Quebec, similar to the kind of plebiscites common in many U.S. states.

The proposal was led by a prominent MNA who argued that if 15 per cent of Quebecers signed a petition to hold a referendum on any topic, including sovereignty, there could be one.

The new policy is part of an effort to win back sovereigntists who question whether PQ Leader Pauline Marois is committed to holding another referendum.

The move shifts the pressure from the party leadership to the general public.

The PQ has faced pressure, since the last referendum in 1995, from its hardline wing eager for another shot.

But the party's leaders have been reluctant to commit to a rematch, with opinion polls suggesting the majority of the public is wary of another battle.

It's not clear, however, how exactly a citizen-led referendum would work _ or whether 15 per cent of the population would be all that's required to force one.

Speaking with reporters after the convention, Marois wouldn't commit to specifics.

"This issue isn't resolved and we'll need to debate it in the National Assembly," she said.

The policy was one of a series of measures approved by the party's delegates at a three-day convention devoted to "changing politics" that wrapped up Sunday in Montreal.

PQ delegates also came up with a plan to deal with political defectors.

The party has seen seven MNAs jump ship in the past few months, with several joining the popular new Coalition for Quebec's Future.

The adopted policy would ban switching parties in the middle of a term and require defectors to sit as independents.

Delegates also approved a proposal to lower the legal voting age to 16.

Dropping the voting age has long been debated within the PQ and young people are traditionally among the sovereignty movement's strongest supporters.

The proposal was contentious, with several young delegates arguing young people aren't usually informed enough to cast a ballot.

The party agreed the change would only take place after history and citizen education programs in the province's schools were improved.

After weeks of speculation, Marois now appears set to lead the PQ unopposed into the next election.

Former Bloc Quebecois chief Gilles Duceppe had been her rumoured replacement until he announced last weekend he wasn't going to return to active politics.

A new opinion poll released Saturday suggested the recent infighting at the PQ hasn't hurt their standing with voters.

The party placed a close third behind Premier Jean Charest's Liberals and the Coalition for Quebec's Future, which continues to lead the polls.

Loading Slideshow

• Jean Charest - 26 per cent approval

  Quebec's Liberal Premier is Canada's least popular. (<a href="http://www.angus-reid.com/wp-content/uploads/2011/12/2011.12.19_Premiers_CAN.pdf">Data from Angus Reid Survey</a>)

• Dalton McGuinty - 38 per cent approval

  Ontario's Liberal Premier is second from bottom on the list of Canadian provincial leaders.

• Darrell Dexter - 39 per cent approval

  Nova Scotia's NDP Premier is third from the bottom.

• Christy Clark - 40 per cent approval

  B.C.'s Liberal Premier is near the middle of the pack.

• David Alward - 40 per cent approval

  New Brunswick's Progressive Conservative Premier is near the middle of the pack.

• Greg Selinger - 50 per cent approval

  Manitoba's NDP Premier is near the middle of the pack.

• Alison Redford - 53 per cent approval

  Alberta's Progressive Conservative Premier is third from the top.

• Kathy Dunderdale - 60 per cent approval

  Newfoundland and Labrador's Progressive Conservative Premier is second from the top.

• Brad Wall - 71 per cent approval

  Saskatchewan's Saskatchewan Party Premier is Canada's most popular.