Last week, the Senate Homeland Security and Governmental Affairs Committee voted 8-7 to advance his nomination, again mostly along party lines. Committee Chair Sen. Rand Paul (R-Ky.) and Democrat Sen. John Fetterman (Pa.), crossed party lines, with Rand in opposition, and Fetterman in favor, of Mullin’s confirmation.  

Noem is expected to depart the agency by March 31. 

Energy executive Alan S. Armstrong, a Republican who had been executive chairman of Williams, a leading natural gas company based in Oklahoma, and its former 14-year CEO, was sworn in to replace Mullin in the Senate, He will serve until January 2027, the end of Mullin's term. Under state law, Armstrong had to pledge not to run for the seat in November.  He noted plans to drive “better policies that allow us to take advantage of our natural resources around the country,” particularly through permit reform legislation to expedite energy projects.

Mullin took bipartisan heat during his March 18 confirmation hearing. Several lawmakers raised questions about Mullin’s temperament and were skeptical about his willingness to steer the agency in a different direction. 

Prior to the committee vote, ranking member Gary Peters (D-Mich.) said, “I’m very troubled by Sen. Mullin’s willingness to condone political violence, and the message that sends to DHS,” adding, “I will be voting no.” 

Paul raised similar concerns, citing Mullin’s unwillingness to condemn a violent incident in 2017 in which a neighbor assaulted the committee chair, breaking several of his ribs and requiring hospitalization.  

But some Republican members signaled support for Mullin. Sen. Bernie Moreno (R-Ohio), said, “Maybe you’re not going to replace Shakespeare as the next greatest orator on Earth, but you talk from the heart, and that’s okay, you are who you are …sometimes we’re imperfect … and I think that’s what people like about you, frankly.” 

Mullin appeared at times belligerent in his responses to lawmakers’ questions, saying he does not condone political violence and characterized some of the arguments being made against him as “political theater.” He said he “regretted” his statements disparaging Renee Good and Alex Pretti after their fatal shootings by federal agents in Minnesota. “Those statements probably should have been retracted … I went out there too fast,” but he added that the investigations into those incidents were still ongoing. 

In his prepared remarks, he said, “I will work hard … My goal is to let people know that we are out there, supporting them.” He added: “We want to bring back confidence and peace of mind about the department.” 

A continual refrain during the hearing was funding for Homeland Security, which has been held up over fundamental disagreements about conduct requirements for Immigration and Customs Enforcement agents. In recent weeks, Democrats have failed to advance a package that would fund all of its agencies apart from the office of the secretary and ICE, while lawmakers still work out their differences in how immigration agents should be managed.  

“If Republicans really do agree with us that [Transportation Security Administration] and other personnel need to be paid, then they should join us and pass the bills to pay them today while we continue to negotiate ICE reforms," said Peters. "Let me be clear: these are very straightforward reforms we’re asking for, we just want ICE to follow the same rules that our local police already do."

Mullin noted that he would not follow Noem’s policy of requiring any funding requests for disaster response and recovery valued over $100,000 to be reviewed by the department secretary, stating that he did not support holding up funding for critical construction repairs and response efforts. He added that this view came as someone who has worked in construction—Mullin was president and owner of his family-run plumbing business, Mullin Plumbing in Broken Arrow, Okla., near Tulsa, before he was first elected to Congress in 2012 as a member of the House, then joining the Senate after winning a 2022 special election to succeed Republican Jim Inhofe, who retired. The firm was sold in 2021 to a residential home services company.

Kristen Swearingen, vice president of government affairs at the Associated Builders and Contractors, said in an email to ENR that Mullin was a group member. “He protects small business and believes in free enterprise."