Contesting the appointment of Acting Attorney General Matthew Whitaker, three Senate Democrats claim in a federal complaint Monday that President Donald Trump circumvented the rigors of a Senate confirmation fight.

“Because the Senate has not consented to Mr. Whitaker serving as an officer of the United States, his designation by the president to perform the functions and duties of the attorney general violates the appointments clause,” the 17-page complaint states. “Indeed, if allowed to stand, Mr. Whitaker’s appointment would create a road map for the evasion of the constitutionally prescribed Senate advice-and-consent role.”

Trump removed former Attorney General Jeff Sessions on Nov. 7 after months of publicly expressing his distaste for the former senator and high-profile Trump surrogate. In a tweet Trump announced he was installing Whitaker, then Sessions’ chief of staff, as the new attorney general.

But Senators Richard Blumenthal, D-Conn.; Sheldon Whitehouse, D-R.I.; and Mazie Hirono, D-Hawaii, say Justice Department succession rules require Deputy Attorney General Rod Rosenstein to take Sessions’ job. Whitaker, after all, has not faced any vote from the Senate, depriving the senators, all of whom sit on the Judiciary Committee, of their advice and consent responsibilities.

Without going through the Senate confirmation process, the lawmakers say Whitaker has so far been able to dodge questions about his legal views, his involvement with a company under investigation by the FBI, and his opinions on Special Counsel Robert Mueller’s investigation into Russian interference in the 2016 presidential election and potential collusion with the Trump campaign.

“Donald Trump cannot subvert the Constitution to protect himself and evade accountability,” Hirono said in a statement Monday. “We want the court to make clear that the Senate must confirm Matthew Whitaker’s appointment as acting attorney general – otherwise this temporary appointment violates the Constitution’s appointments clause. Without exception for President Trump’s allies, principal officers who report directly to the president must be subject to a hearing and confirmed by the Senate.”

The senators are represented by a group of attorneys from the Protect Democracy Project and the Constitutional Accountability Center.

The Justice Department said in reaction Monday that the claims by the senators “ignore centuries of practice and precedent.”

“President Trump’s designation of Matt Whitaker as acting attorney general of the United States is lawful and comports with the Federal Vacancies Reform Act, the appointments clause of the U.S. Constitution, Supreme Court precedent, past Department of Justice opinions, and actions of U.S. presidents, both Republican and Democrat,” Justice Department spokeswoman Kerri Kupec said in a statement. “There are over 160 instances in American history in which non-Senate confirmed persons performed, on a temporary basis, the duties of a Senate-confirmed position.”