By ERIC TUCKER

WASHINGTON (AP) — President Donald Trump’s executive orders targeting the legal community pose “a grave threat to our system of constitutional governance and to the rule of law itself,” according to a court filing submitted Friday by more than 500 law firms.

The brief represents the most organized pushback to date against a series of White House executive orders that have sought to punish some of the country’s most elite firms and to extract concessions from them. Some of the targeted firms have sued to halt enforcement of the orders, while others have struck deals with the White House either to avert an order or to have it rescinded.

The filing was submitted as part of a lawsuit filed by Perkins Coie, which is among the firms that have challenged the orders in court. The order against that firm and others demands that security clearances of its lawyers be suspended, that federal contracts be terminated and that employee access to federal buildings be restricted.

The firm won a court order temporarily blocking enforcement of several provisions of the executive order, but its court case is still pending.

On Friday, more than 500 firms and law offices from around the country signed onto a brief urging a judge to permanently block the order. The firms, in their filing, call the order a “grave threat to our system of constitutional governance and to the rule of law itself.”

“The looming threat posed by the Executive Order at issue in this case and the others like it is not lost on anyone practicing law in this country today: any controversial representation challenging actions of the current administration (or even causes it disfavors) now brings with it the risk of devastating retaliation,” the brief argues.

It adds: “Whatever short-term advantage an administration may gain from exercising power in this way, the rule of law cannot long endure in the climate of fear that such actions create. Our adversarial system depends upon zealous advocates litigating each side of a case with equal vigor; that is how impartial judges arrive at just, informed decisions that vindicate the rule of law.”

Last month, Paul Weiss became the first firm to cut a deal with the White House, agreeing to dedicate $40 million in pro bono legal services to causes championed by the Trump administration and to ensure merit-based hiring instead of relying on diversity, equity and inclusion considerations in its employment practices. In exchange, the White House rescinded an executive order issued days earlier.

Since then, the law firms of Millbank and Skadden, Arps, Slate, Meagher & Flom have reached similar agreements to avoid being hit with an executive order.

Several of the targeted firms have been subject to orders, in part, because of their prior or current associations with lawyers who either investigated Trump or are among the president’s perceived adversaries.