Perkins Coie called Howell’s ruling “an important first step in ensuring this unconstitutional executive order is never enforced”.
A White House spokesperson in a statement after Wednesday's hearing cited the Trump administration's efforts against “waste, fraud, and abuse” in the government and said “it is absurd that a billion-dollar law firm is suing to retain its access to government perks and handouts”.
A lawyer for the US justice department, Chad Mizelle, argued at the hearing that the president has broad power to determine that some individuals and companies cannot be trusted with the country's secrets.
The lawsuit marked an escalation of a growing feud between Trump and law firms that he has accused of being aligned against his administration's interests.
Perkins Coie, founded in Seattle, sued Trump's administration on Tuesday, arguing his executive order violated the firm's rights under the US constitution, including protections for free speech, free association and due process.
According to the lawsuit, at least seven Perkins Coie clients, including a major government contractor, have already withdrawn legal work because of Trump's order or were considering doing so, costing the firm “significant revenue”.
Government employees have discouraged or blocked Perkins Coie attorneys from attending meetings due to the order, the lawsuit said.
Trump in February issued another order targeting the law firm Covington & Burling, though his restrictions were not as broad as those against Perkins Coie. Covington is representing Jack Smith, the special counsel appointed during Democratic former president Joe Biden's administration who brought criminal charges against Trump in two cases.
Perkins Coie and Covington are among more than a dozen prominent law firms representing clients in lawsuits challenging Trump administration policies and priorities, including its efforts to curtail immigration, agency grants and transgender rights.
Trump's order against Perkins Coie criticised the firm over its internal workforce diversity and inclusion policies and its work for Hillary Clinton's presidential campaign. Democrat Clinton lost to Trump in the 2016 election that first put him in office.
“We have a lot of law firms that we're going to be going after, because they were very dishonest people,” Trump told the Fox News _Sunday Morning Futures_ programme on Sunday.
**Reuters**