The American Bar Association on Monday sued President Donald Trump, challenging an “intimidation policy” it says the White House is using to try to sideline some of the country’s top law firms.

Trump violated the constitution by targeting law firms through a series of executive orders, the ABA said in the complaint, filed in the US District Court for the District of Columbia. The administration has already prompted some unnamed firms to rethink the cases and clients they take on, according to the group.

“The President’s attacks on law firms through the Law Firm Orders are thus not isolated events, but one component of a broader, deliberate policy designed to intimidate and coerce law firms and lawyers to refrain from challenging the President or his Administration in court, or from even speaking publicly in support of policies or causes that the President does not like,” the ABA said in the Monday filing.

The organization is represented by lawyers from Susman Godfrey, one of the four law firms that sued the Trump administration over executive orders specifically targeting them for ties to attorneys that the president views as enemies. The orders threatened lawyers’ security clearances and access to federal buildings, as well as their clients’ federal contracts.

“This is the time to stand up, speak out and seek relief from our courts,” ABA President William R. Bay said in a statement. “There has never been a more urgent time for the ABA to defend its members, our profession and the rule of law itself.”

The lawsuit seeks a broad order declaring attacks on law firms like those in the executive order unconstitutional.

A White House spokesperson didn’t immediately respond to a request for comment.

The leaders of some advocacy groups say they’ve had a difficult time finding top firms to take their cases since Trump began issuing the executive orders. At least one of the 50 largest largest firms in the country has changed its case intake process and is less willing to take on matters adverse to the administration, the ABA said, citing an unnamed member who works at the firm.

Three firms hit with executive orders—Perkins Coie, Jenner & Block, and WilmerHale—later obtained permanent injunctions against the executive orders, with judges striking them down as unconstitutional. Susman has obtained a temporary injunction and is awaiting a ruling on a request for a final decision.

Nine other firms have pledged a total of nearly $1 billion in free legal services as part of deals to avoid similar orders. They committed to working on causes championed by Trump, including combating anti-semitism, assisting veterans, and “ensuring fairness” in the justice system. Cadwalader, one of the deal-making firms, plans to help the Brooklyn District Attorney defend convictions as a way to satisfy their pledge to Trump.

Latest ABA Fight

The lawsuit marks the latest chapter in the ABA’s ongoing fight with the Trump administration.

The group and its president have steadily increased its criticisms of Trump and administration officials over moves they say jeopardize the rule of law. It also defended its process for vetting judicial nominees after the Justice Department blocked the organization from evaluating President Donald Trump’s picks for the federal bench.

The ABA earlier this year laid off one-third of its workforce after the Trump administration cut $69 million of its grant funding. The organization is waging another suit against the Justice Department as it tries to cut another $3.2 million in federal grants.

Attorney General Pam Bondi in February threatened the ABA’s law school accreditation powers over the accrediting body’s diversity mandate for law schools. Deputy Attorney General Todd Blanche in April barred DOJ employees from participating in the professional organization’s events in their official capacities or on official time.