New Jersey Senator Cory Booker is calling on the Department of Justice to open an investigation into the tactics used by police against peaceful water protectors at the protest site in North Dakota.

Senator Booker penned a letter to A.G. Loretta Lynch and her deputy Vanita Gupta, in which he called on the federal government to pay attention and take action.

Booker called the actions by police “inappropriate,” and urged the government to send federal monitors which would allow the protesters to safely demonstrate as is their constitutional right.

Said Booker:

“[I am] deeply troubled by this tense situation, and particularly by reports indicating that law enforcement may be responding to peaceful protestors near Standing Rock with overly aggressive tactics.”

Booker also raised questions about how arrested protesters were treated, and questioned whether the police were violating human rights and “unconstitutional conditions of confinement.”

The public has repeatedly seen the oil police at these protests instigating violence against peaceful protesters and using non-lethal weapons to nearly lethal result. Hundreds have been arrested and hundreds more have been subjected to torture from the police forces who are working on behalf of a law-breaking corporation.

Meanwhile, the Army Corp of Engineers has announced that on December 5, they plan to evict all water protectors, just a day after hundreds of U.S. veterans are expected to join the protest.

Booker is the first of more mainstream Democrats to step forward and voice his concern over the conditions in the Dakotas. He did not appear to voice an opinion about whether the pipeline should be built, only that those who oppose it should be given the opportunity to safely do so.