On January 2, 2017, protesters rally against the Dakota Access Pipeline in a march behind the 128th Rose Parade in Pasadena, California.Michael Owen Baker / AP

Late on Tuesday evening, as President Donald Trump announced his pick for the Supreme Court, the U.S. Army Corps of Engineers signaled a shocking reversal: It will now allow the Dakota Access pipeline to go forward as planned.

Specifically, at the direction of the acting secretary of the army, the Corps will permit the pipeline to be built under Lake Oahe in North Dakota. This means that the agency will skip an environmental-impact review that it said it would conduct just last month, removing the last bureaucratic hurdle to the pipeline’s construction.

It will not remove the last legal hurdle, however. The Standing Rock Sioux Tribe said Tuesday that it would sue to block the pipeline if the Corps follows through on their announcement.

“The Army Corps lacks statutory authority to simply stop the [environmental-impact statement] and issue the easement,” said the tribe in a statement. “To abandon the [environmental review] would amount to a wholly unexplained and arbitrary change based on the President’s personal views and, potentially, personal investments.”

Some kind of environmental-impact review for the Dakota Access pipeline is required by the National Environmental Policy Act, a federal law passed under President Nixon. Energy Transfer Partners, the company building the pipeline, has not issued a statement.

The apparent reversal continues the saga over the project, which has become a rallying point for Native civil rights and a deepening crisis for federal rule of law. It also illustrates how inescapable Trump’s conflicts of interest are: The president may own as much as $50,000 in stock of Energy Transfer Partners. He has never offered evidence he has divested himself of it.

The Dakota Access pipeline is a proposed 1,100-mile conduit that will connect the oil fields of North Dakota to the ports and refineries of southern Illinois. The pipeline’s route passes almost entirely through private land, and it is already more than 80 percent complete.

But it also crosses Lake Oahe, a federal waterway and a major reservoir of the Missouri River. The Standing Rock Sioux reservation is west of Lake Oahe, and they depend on it as a water source. (Lake Oahe was also created by the Corps of Engineers in the 1960s, when it a botched a dam project and flooded sacred Sioux land.)

Since the spring, the Standing Rock Sioux Tribe has argued that neither Energy Transfer Partners nor the Army Corps of Engineers told the tribe about plans for the project, as the law requires. The Army Corps of Engineers used a national permit designed for wetland areas to approve the pipeline, meaning that the project never got a full environmental-impact review.

The tribe and the Army Corps of Engineers tussled over whether this was legal throughout the summer. Simultaneously, thousands of demonstrators—the majority of them Native people from across North America—set up huge protest camps on the Standing Rock reservation to oppose the pipeline’s construction.  

In early September, a federal judge in D.C. district court released a verdict: The Corps, he said, had behaved appropriately. But minutes later, the Obama administration announced that it was independently reviewing the pipeline’s permits, and it asked Energy Transfer Partners to halt construction.

Three months later, in early December, the Army Corps of Engineers announced that it had made a mistake. The Dakota Access pipeline would get a two-year environmental-impact review after all. “It’s clear that there’s more work to do,” said Jo-Ellen Darcy, then the Army secretary for civil works. “The best way to complete that work responsibly and expeditiously is to explore alternate routes for the pipeline crossing.”

But then, last week, Donald Trump ordered the Corps of Engineers “to review and approve [the Dakota Access pipeline] in an expedited manner.” He also asked the agency to look into withdrawing the environmental-impact requirement “to the extent permitted by law and as warranted.”

The army now appears to be fulfilling that command. The Army Corps appears to not yet have formally issued the easement allowing the construction. Instead, two different congressmen from the state said that the acting secretary for the army informed them that he will order the easement.

“This will enable the company to complete the project, which can and will be built with the necessary safety features to protect the Standing Rock Sioux Tribe and others downstream,” said John Hoeven, a Republican senator of North Dakota.  “Building new energy infrastructure with the latest safeguards and technology is the safest and most environmentally sound way to move energy from where it is produced to where people need it.”

Making sure that the pipeline has “the necessary safety features to protect the Standing Rock Sioux Tribe” is one responsibility of the soon-to-be-skipped environmental-impact review.

Throughout the process, legal experts have stressed that if the president follows proper procedure, he has relatively little power to change the fate of the pipeline.

“The reason these statutory and regulatory procedures are in place is to avoid arbitrary and unconsidered decisions by an executive,” said Monte Mills, a Native law expert at the University of Montana, in November.

After the Corps announced that the pipeline would get a full environmental review, they stressed this point. “It would be really unprecedented for the president-elect to tell the agency to reverse the decision,” Sarah Krakoff, a professor of resource law at University of Colorado Boulder, told me then. “It would cause all kinds of consternation about undue executive interference.”

Now that seems to be exactly what has happened. Under President Obama, the Army Corps of Engineers decided it needed to give the pipeline an environmental-impact review; under President Trump, it immediately ruled the opposite. Federal law is clear that large projects should usually get that review—and, last month, the Army Corps of Engineers decided this project was sufficiently large to deserve it. At some point, politics contravened legal responsibility in this case. Americans might want to know when that happened.

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