Advocates for open border policies are on high alert ahead of long-time President-Elect Donald Trump ally Sen. Jeff Sessions’ (R-AL) likely confirmation to U.S. Attorney General.

In a piece by the Washington Post, the ACLU Immigrants’ Rights Project and the National Immigration Law Center are both quoted as being concerned about what could happen to the current immigration system with Sessions as AG.

“I think it’s disturbing to contemplate what he would do as attorney general,” Director of the ACLU Immigrants’ Rights Project Cecillia Wang told the paper.

Meanwhile, an executive with the National Immigration Law Center voiced a similar fear with Sessions as AG, especially when it came to Trump’s plan to keep migrants from countries rife with Islamic terrorism out of the country:

Karen Tumlin, legal director of the National Immigration Law Center, said she fears that Sessions might even “not feel it was a responsibility of the Justice Department to protect the civil rights of Muslim Americans in this country.”

“It’s not because we quibble on policy,” she said of why she does not support Sessions’ nomination. “It’s because I quibble with the nation’s top lawyer not protecting equality in our country.”

The open borders lobby has long been an enemy of Sessions after his tenure in the Senate Subcommittee on Immigration and the National Interest.

Trump’s immigration plans derive largely from ideas that Sessions has been speaking about for decades while in public office–issues like enforcing E-Verify; closing the country’s southern border with Mexico; and making it more difficult for the Mexican drug cartels and illegal immigrants to pass through unchecked.

Sessions’ former chief of staff from the 1990s, Armand DeKeyser, told the Post how the likely AG’s views on immigration shaped when he went on a “listening tour” in his home state of Alabama.

According to Dekeyser, Sessions spoke with law enforcement officials at the time about how federal agents were filling their local prisons with illegal immigrants, mostly from Central America, who had been captured or committed a crime while living in the country illegally.

“We were not aware of this problem until then,” DeKeyser told the Post. “We didn’t have any idea it was that big a problem. We were surprised at the numbers.”

John Binder is a contributor for Breitbart Texas. Follow him on Twitter at @JxhnBinder.