The law firm Perkins Coie has filed suit against the Trump administration over an executive order signed by President Donald Trump last week that targeted the firm for its work representing Hillary Clinton’s 2016 campaign.

Attorneys representing Perkins Coie filed the lawsuit on Tuesday in the U.S. District Court for the District of Columbia, along with a request for a temporary restraining order to bar enforcement of the executive order.

“The Order is an affront to the Constitution and our adversarial system of justice,” the lawsuit said. “Its plain purpose is to bully those who advocate points of view that the President perceives as adverse to the views of his Administration, whether those views are presented on behalf of paying or pro bono clients.”

It’s the first legal challenge in what Trump has previewed will be a wave of executive actions seeking to punish law firms that have represented his perceived political enemies.

The order, signed by Trump on March 6, mandates that lawyers working for Perkins Coie have their security clearances stripped and aims to terminate any government contracts that might exist with the firm or other entities that it represents. It further bars agencies from hiring employees of Perkins Coie and prohibits employees from the firm from accessing government buildings.

“Perkins Coie brings this case reluctantly,” the lawsuit said. “The firm is comprised of lawyers who advocate for clients; its attorneys and employees are not activists or partisans. But Perkins Coie’s ability to represent the interests of its clients — and its ability to operate as a legal-services business at all — are under direct and imminent threat. Perkins Coie cannot allow its clients to be bullied.”

In his signing of the order, Trump pointed to Perkins Coie’s work in the 2016 campaign and ties to the “Steele Dossier,” which detailed a series of highly salacious allegations about Trump that were later investigated by the FBI and determined to be unsubstantiated.

Marc Elias, who left Perkins Coie to start his own firm in 2021, brokered an agreement with the research and intelligence firm Fusion GPS to conduct opposition research on Trump leading up to the 2016 election. Fusion then hired a former British spy, Christopher Steele, who compiled the dossier.

As Perkins Coie’s lawsuit noted, however, the two attorneys singled out in the executive order’s actual text “have not been with the firm for years.”

“The retaliatory aim of the Order is intentionally obvious to the general public and the press because the very goal is to chill future lawyers from representing particular clients,” the lawsuit said.