Trump may have difficulties reversing Obama's Arctic offshore drilling ban

With a signature, U.S President Donald Trump reversed a key plank in former President Barack Obama's climate change policy signing a presidential memo thatpavesthe way forthe revival ofKeystone XL pipeline project.

But it's going to be difficult for him to do the same with Obama's moratorium on offshore drilling in the Arctic, according to a former lawyer with the Bill Clinton administration.

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"Obama had clear statutory authority to do what he did," John Leshy said in an interview with CBC News.

"The question for President Trump is whether he can reverse that order. The answer's not clear because it's never been tried."

Leshy is a professor emeritus in real property law at the University of California Hastings and served as the solicitor generalin the Department of the Interior during the Bill Clinton administration.

Obama signed the executive order indefinitelyprohibiting drilling in the bulk of U.S-owned waters in the Arctic Ocean in December. Then came asimilar order from Prime Minister Justin Trudeau banning the issuance of any new offshore leases inthe Canadian part of the Arctic Ocean for five years.

That ban was made possible by a provision in a 1953 law that states"the president of the United States may, from time to time, withdraw from disposition any of the unleased lands of the Continental Shelf."

The law has been used before, Leshy said, but most presidents impose time limits that have been tinkered withthough never reversed entirely.The few instances that were set without any limits have not been challenged yet.

"Since it's never been tried, we don't know whether the president has the power [to reverse] that decision," Leshy said.

"Ultimately, I supposethe federal courts will decide whether he does."

The U.S Congress does have the power to overturn the Arctic drilling ban, Leshy said. The question is whether the president can do it on his own.

"If Trump tries to do it without Congress, just on his own, that would certainly be challenged," he said.

"A court could go either way although there are certainly good arguments in favour of the Obama order's permanence and only being reversible by Congress."

Demand for Arctic oil unclear

When Obama announced the Arctic drilling ban, oil industry officials cried foul.

A spokesman for the Independent Petroleum Association of America said at the time the "unilateral mandate could put America back on a path of energy dependence for decades to come."

But only one company Royal Dutch Shell PLC has drilled in those waters in the past decade. It ceased its exploration in the Chukchi and Beaufort seas after spending upward of $7 billion, citing disappointing results from a well drilled in the Chukchi.

"It might be kind of a moot issue," Leshy said.

"The market may have spoken, at least in the short term and say 'What Obama did, at least in the short term, is not a big deal for us since we're not going to be up there anyway.'"