Former Conservative MP Marilyn Gladu has crossed the floor to the Liberals, becoming the latest to switch over to the government caucus and bringing Prime Minister Mark Carney just one seat away from a functional majority.
The move from Gladu, the MP for the Ontario riding of Sarnia—Lambton–Bkejwanong, comes days before three byelections are set to be held that could reset the balance of power in Parliament.
Carney and Gladu both issued statements Wednesday morning to announce the move, with the prime minister saying he was “honoured” to welcome Gladu into the Liberal caucus.
Gladu said she had heard from her constituents that they want “serious leadership and a real plan” for the economy, and that she had made “a choice to do the best thing for our community’s priorities, and importantly, for our country.”
Speaking to reporters in Ottawa on Wednesday, Gladu said Carney had “invited me to bring my experience, my talents and my views into the large Liberal tent, and I think that will have a better effect inside than it will outside.”
“We need a serious leader who can address the uncertainty that has arrived due to the unjustified American tariffs,” she said. “We need a global leader with a plan to make a more resilient Canada, a stronger Canada, a more self-reliant Canada for this critical moment.
“That man is our prime minister, Mark Carney.”
Carney highlighted Gladu’s engineering and business experience and called her “one of the most collaborative members of Parliament, working across party lines on important issues” since she was first elected in 2015.
“(She’s) really dedicated to her electors in Sarnia—Lambton–Bkejwanong, which I am informed rightly means ‘where the waters meet,’” he said. “And the waters, in my analogy, are meeting in service of Canadians at this crucial time for our country.
“We couldn’t be happier to have this expertise, experience and energy coming to our team.”
Gladu previously ran for the Conservative leadership in 2020 and is an engineer by trade.
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She has also generated controversy in the past with her public comments and social conservative views.
During the COVID-19 pandemic, she was criticized by then-Conservative leader Erin O’Toole for downplaying the severity of the virus and the safety of vaccines in an interview. She later apologized.
Gladu also appeared to promote unproven treatments for COVID-19 and pushed for workplaces to reopen at the height of the pandemic, in comments she later said were taken out of context.
While running for the Conservative leadership in 2020 against O’Toole, Gladu said she would allow caucus members to bring forward private members bills to restrict abortion, saying it would allow for “healthy discussion.”
Gladu also sparked an angry response from the Mexican government in 2018 when she implied that many Mexican visitors to Canada are involved in the illegal drug trade.
That statement came during debate over legislation that ultimately made marijuana legal across Canada, a policy Gladu opposed.
After Conservative Leader Pierre Poilievre won the party leadership in 2022, Gladu said in a statement that she was “proud to have supported him every step of the way, and looking forward to uniting our party under his leadership.”
Poilievre has yet to comment on Gladu’s decision to cross the floor.
Gladu’s crossing to the Liberals puts the governing party at 171 seats in the House of Commons — just one seat shy of a functional majority.
That would require House of Commons Speaker Francis Scarpaleggia to break ties when voting on legislation and motions. Although Scarpaleggia is a Liberal MP, he is not guaranteed to side with his party.
If the Liberals get 173 seats, that would secure a slim but “full” majority government that does not rely on the Speaker breaking ties.
Byelections are set to be held in three ridings Monday, including Terrebonne, the Quebec riding where last year’s election was called for the Liberal candidate by one vote. The Supreme Court of Canada later nullified the result after a challenge from the Bloc Quebecois.
While Terrebonne remains a toss-up between the Liberals and the Bloc, the other two byelection ridings — Scarborough Southwest and University–Rosedale, both in the Greater Toronto Area — are considered safe Liberal seats.
Carney’s Liberals were elected to government last April with 170 seats, including Terrebonne. Several Liberal MPs have also retired since then, fluctuating their seat count.
Since December, three other former Conservative MPs — Chris d’Entremont, Michael Ma and Matt Jeneroux — have crossed the floor to the Liberals, while Lori Idlout switched from the NDP to join the government caucus last month.
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