President Trump, in a tweet Tuesday, said he will nominate Chad Wolf, the acting secretary of the Department of Homeland Security, to be DHS secretary.

The announcement comes less than two weeks after the Government Accountability Office concluded that Wolf and Ken Cuccinelli, the senior official performing the duties of DHS deputy secretary, were not appointed through a valid process. They have been serving in their roles since November without Senate confirmation.

The last Senate-confirmed official to hold the post was Kirstjen Nielsen, who resigned in April 2019.

"Chad has done an outstanding job and we greatly appreciate his service!" Trump said in his tweet.

Not long afterward, Wolf responded to the nomination on Twitter.

"Honored to be nominated by @POTUS to lead the men & women of DHS in safeguarding the American people," Wolf wrote.

"As the Homeland faces evolving threats from natural disasters, violent opportunists, malign cyber actors & transnational criminal orgs, the mission of DHS is as critical as ever."

The president has previously said he prefers temporary appointments because it allows him to circumvent the Senate's confirmation process of senior administration officials.

The GAO's Aug. 14 assessment was grounded in the fact that Wolf's and Cuccinelli's appointments were the result of the actions of an earlier official, Kevin McAleenan, who was improperly placed in charge of the DHS due to an error in paperwork by Nielsen.

More specifically, to pave the way for McAleenan in a manner that allowed him to eschew Senate confirmation, Nielsen amended the annexes to an executive order, instead of amending the executive order itself.

Days after the GAO's finding, DHS called the assessment "baseless and baffling" in an eight-page letter. It also called for the GAO's report to be rescinded, saying the office lacks the authority to opine on any appointments made under the Homeland Security Act of 2002 — the means by which Wolf and Cuccinelli have both been granted their temporary posts. Some legal experts have pointed out that the GAO's opinion is not binding on either DHS or the court system.

Under Wolf's leadership, DHS attracted scrutiny for deploying federal agents to protests in Portland, Ore., as well as new restrictions on asylum-seekers and Deferred Action for Childhood Arrivals, or DACA, applicants. Those who have filed lawsuits seeking to throw out DHS actions on the grounds that the department's leadership is not legitimately in power now have an additional cudgel.

"There is no valid argument that Wolf's use of the title 'acting secretary' is lawful," John Sandweg, the DHS' former acting general counsel, said in a statement.

Sandweg added that Wolf's appointment also exceeds the Vacancies Reform Act's 210-day limit on acting officials.

It is unclear if the GOP-controlled Senate will vote to confirm Wolf, who was previously confirmed by the chamber to be DHS undersecretary for strategy, policy and plans. A Republican lawmaker told reporters Tuesday that while he remained a supporter of Wolf, he was not clear on the Senate landscape for his nomination.

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