As peaceful prayer camps grow in North Dakota against the controversial Dakota Access Pipeline, demonstrators in Washington, D.C. are marching and chanting in solidarity while a U.S. federal court hears arguments regarding the Standing Rock Sioux tribe's motion to halt pipeline construction.

"This is just one battle. Regardless of the outcome, we hold our heads high, and we move forward."
—Standing Rock Sioux Chairman David Archambault II

In its motion (pdf), the tribe argues that the U.S. Army Corps of Engineers violated several federal laws by approving the pipeline, and seeks preliminary injunctive relief to halt the pipeline construction.

The tribe says that the pipeline will destroy sacred lands and threaten their access to clean water.

"If the judge grants the preliminary injunction, what we can anticipate is that the Energy Transfer Company and possibly the Department of Justice will file an appeal," said Standing Rock Sioux Chairman David Archambault II to Indian Country Today Media Network. "They can appeal. But they won't be able to continue construction."

A federal judge is expected to issue a ruling Wednesday.

While the hearing goes on, Indigenous people from various tribes around the country as well as Hollywood stars are gathering outside of the courthouse to declare solidarity and demand justice for the Standing Rock Sioux.

"This movement is international, because clean water is life," one demonstrator declared.

Participants tweeted videos and photos from the action under the hashtags #NoDAPL, #RezpectOurWater, and #StandWithStandingRock:

Tweets about #NoDAPL OR #RezpectOurWater OR #StandWithStandingRock

"This is just one battle," Archambault told Indian Country Today. "Regardless of the outcome, we hold our heads high, and we move forward."