Acting Homeland Security Secretary Chad Wolf on Monday became the latest Cabinet official to step down following last week's deadly riot at the U.S. Capitol.
"Unfortunately, this action is warranted by recent events, including the ongoing and meritless court rulings regarding the validity of my authority as Acting Secretary," Wolf wrote in a letter to staff members obtained by NBC News. "These events and concerns increasingly serve to divert attention and resources away from the important work of the Department in this critical time of a transition of power."
Wolf said his resignation would become effective at midnight. Pete Gaynor, administrator of the Federal Emergency Management Agency, will take over as acting secretary.
The mob attack in Washington as Congress was affirming President-elect Joe Biden's win resulted in the deaths of five people, including a Capitol Police officer. Several other Cabinet officials have already resigned, including Transportation Secretary Elaine Chao and Education Secretary Betsy DeVos, who both cited President Donald Trump's role in egging on the rioters. Wolf, who did not specifically cite the riots in explaining his decision to leave, issued a strong statement Thursday condemning the rioters.
"What transpired yesterday was tragic and sickening," he said. "While I have consistently condemned political violence on both sides of the aisle, specifically violence directed at law enforcement, we now see some supporters of the President using violence as a means to achieve political ends. This is unacceptable. These violent actions are unconscionable, and I implore the President and all elected officials to strongly condemn the violence that took place yesterday."
The White House announced last week that it was withdrawing Wolf's nomination to be permanent secretary shortly after his statements critical of Trump.
Threats of further unrest tied to Biden's swearing in next week are causing alarm. A senior law enforcement official said the FBI sent a memo to law enforcement agencies across the country warning of possible armed protests at all 50 state capitols and in Washington starting Saturday.
Wolf faced many challenges during his brief tenure, including overseeing the construction of hundreds of miles of Trump's long-promised border wall, which has fallen short of what Trump promised. Trump is set to travel to Texas on Tuesday to visit a section of the wall.
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Wolf's time as acting secretary has also been marked by civil unrest, the coronavirus pandemic and the escalation of the Trump administration's immigration policies. He has also faced scrutiny over how the Department of Homeland Security handled intelligence assessments and a $6 million contract that was awarded to his wife's company.
Wolf has been acting secretary since November 2019. The last homeland security secretary to be confirmed by the Senate, Kirstjen Nielsen, resigned in April 2019. Although Trump formally nominated Wolf for the job last summer, Wolf has yet to get a full vote in the Senate, remaining acting secretary.
A federal judge ruled in November that Wolf has not been acting lawfully as the secretary of homeland security and that, as a result, his suspension of protections for a class of migrants brought to the United States illegally as children is invalid. The judge reaffirmed the ruling last month and reinstated the Obama-era Deferred Action for Childhood Arrivals program, which Trump has tried to end.