The latest decision in a long-running legal battle against the Dakota Access Pipeline (DAPL) has delivered yet another victory to the Standing Rock Sioux Tribe. The U.S. Court of Appeals for the D.C. Circuit issued a ruling today upholding a federal court’s decision that the U.S. Army Corps violated key environmental laws and requiring a full environmental impact statement (EIS) to study the risks the controversial oil infrastructure poses to the Standing Rock Sioux Tribe. The EIS will examine risks of an oil spill and evaluate alternative routes that don’t impose risks on the Tribe.

In practical terms, since the Court did not require a shutdown, this decision means the pipeline continues to operate illegally. A federal permit granting easement for the pipeline to cross beneath Lake Oahe — on unceded ancestral Tribal lands nearby the Standing Rock Sioux reservation — will remain invalid until the conclusion of the EIS process, when the Corps must decide whether to re-issue the permit. In the meantime, the Tribe continues to pursue its case in federal court, where it has filed for an injunction to shut down the pipeline while the environmental review is underway.

Under the Trump administration, the U.S. Army Corps took no enforcement action against Dakota Access for continuing to operate without a permit. The Biden administration has discretion to issue an interim shutdown order to bring the pipeline into compliance with federal law while the EIS proceeds.

“We are pleased that the D.C. Circuit affirmed the necessity of a full environmental review, and we look forward to showing the U.S. Army Corps of Engineers why this pipeline is too dangerous to operate,” said Standing Rock Sioux Tribe Chairman Mike Faith.

“Today we’ve reached another milestone in our four-year legal battle on behalf of the Standing Rock Sioux to shut down this pipeline,” said Earthjustice attorney Jan Hasselman. “This decision affirms what the Tribe has been saying from the start — this pipeline is a threat to clean water and Indigenous sovereignty, and we must examine the consequences it brings for the future.”