Canada’s western-most province has sued Alberta over a new law that would allow Alberta to cut off gas supply to British Columbia if the Trans Mountain expansion project isn’t moved forward.

“My hope is that we don’t have to use this power,” Alberta Premier Jason Kenney said at a conference on Wednesday, after announcing the previous day his cabinet had proclaimed Bill 12 as law at its first meeting.

“I’ve always said we want to start by trying to build relationships, find common ground, and not start immediately with our highest card to play.”

The “turn off the taps” legislation, first introduced by the NDP government and given royal assent last year, would enable Alberta to curtail oil shipments to B.C. Kenney promised on the campaign trail to show B.C. the bill was not a bluff.

On Wednesday, B.C. Premier John Horgan said he, too, was confident his province and Alberta could work together and both provincial leaders called a private conversation Tuesday night respectful and diplomatic.

But a statement of claim dated May 1 and filed in Calgary by B.C.’s attorney general on behalf of B.C. residents calls Bill 12 unconstitutional.

The lawsuit argues the bill—by which Alberta’s minister of energy would require exporters of crude oil, natural gas and refined fuels to obtain licenses—is beyond provincial jurisdiction because it would result in discrimination in prices or supplies to B.C. The Constitution Act, 1867, mandates products from the provinces move freely between each other.  

“What we’re in court doing is asserting our right to regulate products that move within British Columbia,” Horgan told press Wednesday.

“I believe that’s in the interest of our marine environment, our natural environment, that British Columbia would have a say in what comes in and what goes out.”

The lawsuit also alleges “the real purpose of the Act is to punish British Columbians for the perceived position of the Government of British Columbia in relation to the Trans Mountain Expansion Project.”

Kenney told reporters he was asking Horgan to respect British Columbians who want to see the project built: “At least get out of the way and stop trying to obstruct it by withholding permits and challenging it every step of the way in the courts.”

However, Horgan insisted B.C. hasn’t thwarted the process. According to its premier, B.C. has issued 309 of 1,182 permits, denying only those that oppose provincial interests.

“Mr. Kenney, who has been on the job for a day and is just decompressing from the high rhetoric of campaigns, is saying something that’s not correct.”

NDP and, now, Opposition Leader Rachel Notley told CTV News she advised Kenney not to proclaim Bill 12 for fear of rendering it useless pending a court ruling.

“Even Mr. Kenney has noted that the majority of B.C. residents now support TMX,” she said on Wednesday. “The UCP government put that at risk choosing, what I would argue, a political posturing over Alberta’s energy industry.”

She added: “He has made it clear he is more interested in optics than getting the job done.”

Notley said her government was aware there was an argument to be made against the legislation, and refrained from making it law in 2018 because B.C. would have been sure to immediately challenge it “at the time when things were very tense.”

“Speaking as someone who just lost the election, I think Mr. Kenney obviously has a firm grasp of politics. But I think we have to remember that you also, once you get into this position, have a job to do the best you can for the people who elected you.”

Neither Kenney nor Horgan are revealing their next plays.

Kenney wouldn’t say what action by B.C. would galvanize Alberta to use Bill 12, only that it was the “final, not the first step.”

“When you’re in a game of poker, you don’t show the other folks at the table what your high card is. You don’t play that high card on the first hand,” Kenney said, insisting his government’s first intent is to find common ground.

“My hope is that the British Columbia government will, frankly, listen to reason and listen to British Columbians and help us get gas prices down,” he added, referencing rocketing fuel prices in the B.C. lower mainland, which he believes would fall if the Trans Mountain expansion was built and increased export capacity for refined products.

Meanwhile, Horgan stayed mum on what B.C. would do if the lawsuit did not conclude in its favour.

“Well again, when you’re playing poker, you should keep your cards in your hands as you need to play them.”

One University of British Columbia law professor told CTV News he believes the courts will find Bill 12 unconstitutional.

“While the law on its face is neutral, the courts in assessing the purpose of a law always look to the broader context,” said Joel Bakan. “And the broader context here is, very clearly and on the record, that Alberta is targeting B.C.”