WASHINGTON — The White House on Tuesday fired John Mitnick, the general counsel for the Department of Homeland Security, after months of shake-up at an agency responsible for carrying out President Trump’s immigration agenda.
“We thank John for this service, and we wish him well,” a department spokeswoman said Tuesday night.
The White House this year has turned the Department of Homeland Security — which oversees securing the country’s borders, disaster relief efforts and addressing domestic terrorism and cybersecurity threats — into a revolving door of officials, creating a void of permanent leadership.
A Trump administration official said Tuesday evening that Chad Mizelle, an associate counsel to the president, would replace Mr. Mitnick. But a Department of Homeland Security official said later that Joseph B. Maher, the department’s principal deputy general counsel, would be taking over.
In April, the White House purged multiple senior homeland security officials, including the secretary, Kirstjen Nielsen and the acting deputy secretary, Claire Grady.
The White House made it clear at that time that Mr. Mitnick and L. Francis Cissna, then the head of United States Citizenship and Immigration Services, or U.S.C.I.S., would also soon be ousted. Mr. Cissna left a month later.
Mr. Mitnick’s ouster was prompted by the White House general counsel’s office as opposed to Stephen Miller, who has been a main force behind previous homeland security firings, an administration official said. But two other people briefed on the events disputed this account, saying that the counsel’s office had tried to keep Mr. Mitnick where he was.
The heads of each agency overseeing immigration or border security — U.S.C.I.S., Immigration and Customs Enforcement and Customs and Border Protection — are each led by officials serving in an acting capacity. The acting secretary of the Department of Homeland Security, Kevin K. McAleenan, has yet to be nominated.
Mr. Mitnick’s exit comes as the department fights off multiple lawsuits challenging Mr. Trump’s immigration policies.
In recent weeks, the Department of Homeland Security has put into effect a rule that would prevent most migrants from obtaining asylum at the southwestern border and unveiled a regulation that could abolish a 20-day limit on detaining children, and it continues to face legal challenges for using Defense Department funding to construct the president’s long-promised border wall.
Homeland security officials, including Mark Morgan, the acting commissioner of Customs and Border Protection, have also recently publicly criticized the judicial system after a judge imposed a block on a policy that would restrict asylum at the border. He described the decision as “judicial activism.”
“Every time this administration comes up with what we believe is a legal rule or policy that we believe will address this crisis,” Mr. Morgan said, “we just end up getting enjoined.”
The Supreme Court this month allowed that policy, which would force migrants hoping to obtain protections in the United States to apply and be denied asylum in at least one country on their way to the southwestern border, to move forward.
Mr. Mitnick was the fifth general counsel for the Department of Homeland Security.