Attorneys general from 16 states and Washington, D.C., criticized President Trump’s temporary pick to lead the Consumer Financial Protection Bureau (CFPB) in a Tuesday letter, saying White House budget director Mick Mulvaney should be disqualified from leading the agency.

Led by New York Attorney General Eric Schneiderman (D), the state law enforcement chiefs said they’d fight any attempt from Trump to weaken the CFPB. 

“The CFPB has been a critical partner in protecting American consumers and holding fraudsters accountable. It deserves a leader who actually believes in its mission,” Schneiderman said.

 “However, Attorneys General won’t hesitate to protect those we serve – with or without a partner in Washington.”

Trump appointed Mulvaney to be acting CFPB director after former Director Richard Cordray resigned in November to run for governor of Ohio. Mulvaney, a staunch conservative, had sponsored bills to eliminate the CFPB while in Congress, and called the bureau “sick, sad” joke.

Democrats and progressive allies of the CFPB have said Trump’s appointment of Mulvaney is an illegal attempt to destroy the bureau, which had aggressively regulated and penalized financial services companies under Cordray.

The 17 attorneys general said the acting director’s previous comments about the CFPB “should disqualify Mr. Mulvaney from leading the agency, even on an acting basis.”

“Such statements about an agency that has helped millions of American consumers and achieved fundamental reform in a number of critically important areas of American commerce are categorically false,” the letter reads.

There have been several unsuccessful legal challenges to Trump’s appointment of Mulvaney.

CFPB Deputy Director Leandra English, who Cordray tapped to be the acting director, filed a complaint in the U.S. District Court for the District of Columbia against Trump and Mulvaney.

English’s complaint claimed that she is the rightful acting director of the CFPB, and that the court should bar Mulvaney from taking the post. English claimed that the provision of the Dodd-Frank Act that lays out the CFPB’s line of succession supersedes the Federal Vacancies Act, which Trump used to nominate Mulvaney.

Judge Timothy Kelly rejected English’s motion two weeks ago, but she filed an injunction against the ruling Wednesday. If the court declines to suspend Mulvaney’s appointment, English is expected to appeal the ruling.