Alberta premier-designate Jason Kenney is threatening to enact the NDP's turn-off-the-taps legislation, which was tabled by outgoing Premier Rachel Notley's government.

Bill 12 would restrict Alberta's oil and gas shipments to B.C. if the province continues to stand in the way of the Trans Mountain Pipeline expansion.

Kenney ran on his support for the pipeline, which included enacting the legislation.

Joel Bakan, a law professor at the University of British Columbia, said there is no constitutional basis for cutting off gas between provinces.

"I can say with absolute confidence that Alberta will lose this case," Bakan said.

The Constitution Act of 1867 says that a province cannot interfere with interprovincial trade and commerce, he said.

"Over the years, the courts have carved out ways in which provinces can take care of their own [legitimate] interests ... but there is no authority for provinces to actively discriminate or retaliate against a province by cutting off interprovincial trade."

Bakan anticipates the bill will become law, but says B.C. will go to court the same day to challenge it, which B.C. Attorney General David Eby has already said he will do.

"From a legal perspective, it's a fairly open and shut case,"Bakan said.

Jason Kenney has said he would enact the NDPs turn-off-the-taps legislation — which was tabled by outgoing Alberta Premier Rachel Notley's government. (CBC/Canadian Press)

What a turn-off-the-taps law would look like

If passed, the turn-off-the-taps law would create a licensing scheme, said Bakan. Alberta suppliers that want to provide B.C. with oil would have to get a licence, giving the Alberta government the ability to deny licences.

"It creates a regime that allows the government to control when, how and if shipments go to B.C," he said.

According to the National Energy Board, most of the gasoline consumed in B.C. comes from Alberta, delivered primarily through the Trans Mountain Pipeline.

Bakan says it's not just the B.C. government that would challenge a turn-off-the-taps law. Distributors from the private sector and suppliers in Alberta will most likely challenge it in court as well.

"It's an economic hit to them because they are losing a market," Bakan said.

Kathryn Harrison, a professor of political science at UBC and an expert on climate policy, agrees Alberta will not be able to fix its economic problems with a shut-off-the-taps law.

"Alberta cannot get the Trans Mountain pipeline built. It's not within their authority," Harrison told Stephen Quinn, the host of CBC's The Early Edition.

"It's a federal decision and it's before the courts what authority B.C. might have to to complicate the transport of some heavy oil across the province."

Listen to the full interview with Kathryn Harrison here:

With files by The Early Edition and Yvette Brend.