The departure of White House chief of staff John Kelly John Francis KellyMORE is raising concerns about how the White House will face potential legal and political challenges in 2019.

Kelly, who was thought to bring order to an often chaotic White House, will leave the West Wing as special counsel Robert Mueller Robert (Bob) MuellerCNN's Toobin warns McCabe is in 'perilous condition' with emboldened Trump CNN anchor rips Trump over Stone while evoking Clinton-Lynch tarmac meeting The Hill's 12:30 Report: New Hampshire fallout MORE's probe into Russian interference in the 2016 election appears to be closing in on President Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE.

Trump will also face a divided Congress next year, with Democrats slated to take control of the House in January, giving the party subpoena power.

ADVERTISEMENT

Sen. Chris Murphy Christopher (Chris) Scott MurphyDemocratic senator calls for 'more flexible' medical supply chain to counter pandemics The Hill's 12:30 Report - Presented by Facebook - Don't expect a government check anytime soon GOP chairman to release interim report on Biden probe 'in about a week' MORE (D-Conn.) said Sunday on ABC's "This Week" that he's concerned Mueller may be on the "chopping block" after the departure of Kelly.

"I imagine that [Kelly] was one of the people that was attempting to convince the president not to fire Mueller, to not issue pardons as a means of trying to influence the investigation."

"And so I think with his departure, certainly depending on who replaces him, our concerns that Mueller may be on the chopping block are more serious and this legislation becomes more important," he added.

Sen. Chris Murphy says with John Kelly's departure, he is concerned Mueller could be on "the chopping block" more seriously.



"I'm certainly going to look at all of our options to try to force a vote on legislation that would protect the special counsel" https://t.co/rAYCRSx9Yv pic.twitter.com/c7dfvPXnfx — ABC News Politics (@ABCPolitics) December 9, 2018

Kelly, a retired four-star general, was viewed as having brought a level of stability to a White House filled with turmoil.

He was also thought to have been able to scale back Trump's decisions, as he imposed a number of restrictions on the president after he took over the reins as chief of staff from Reince Priebus Reinhold (Reince) Richard PriebusLeaked audio shows Trump touted low Black voter turnout in 2016: report Meadows joins White House facing reelection challenges Trump names Mark Meadows as new chief of staff MORE last year. Kelly reportedly limited Trump's access to his personal cell phone and limited impromptu visits to the Oval Office among aides.

Outgoing Speaker Paul Ryan Paul Davis RyanKenosha will be a good bellwether in 2020 At indoor rally, Pence says election runs through Wisconsin Juan Williams: Breaking down the debates MORE (R-Wis.) in a statement on Saturday called Kelly a "force for order, clarity, and good sense."

“Our country is better for his duty at the White House. During this time he has become a dear friend and trusted partner," Ryan said. "He was a force for order, clarity, and good sense. He is departing what is often a thankless job, but John Kelly has my eternal gratitude.”

Sen. Marco Rubio Marco Antonio RubioOvernight Defense: Pentagon redirects pandemic funding to defense contractors | US planning for full Afghanistan withdrawal by May | Anti-Trump GOP group puts ads in military papers Democrats step up hardball tactics as Supreme Court fight heats up Press: Notorious RBG vs Notorious GOP MORE (R-Fla.) told CNN’s "State of the Union" on Sunday he didn't know yet whether he should be concerned about the order and stability of the White House after Kelly's exit.

“It depends who they put in as a replacement,” he said. "Hopefully it will be someone just as qualified, just as strong. It's good for our country to have someone like that in that post."

Trump announced Kelly's departure on Saturday, calling him a "great guy" and saying he will leave at the end of the year. His replacement is expected to have a more political focus than Kelly ahead of 2020.

Rumors of hot-tempered disputes with other staffers have dogged Kelly's tenure, and he has been criticized over his handling of domestic abuse allegations against former White House staff secretary Rob Porter, among other situations, which means not everyone is unhappy to see Kelly exit.

Rep. Yvette Clarke Yvette Diane ClarkeLawmakers call for small business aid at all levels of government The Hill's Morning Report - Sponsored by Facebook - Washington on edge amid SCOTUS vacancy The Hill's 12:30 Report - Presented by Facebook - Top tech executives testify in blockbuster antitrust hearing MORE's (D-N.Y.) response on Sunday was "thank u, next."

She said Kelly "destroyed his reputation" by making false allegations in the past, apparently referring to comments he made last year about Rep. Frederica Wilson (D-Fla.).