Rep. Adam Schiff Adam Bennett SchiffChris Matthews ripped for complimenting Trump's 'true presidential behavior' on Ginsburg Trump casts doubt on Ginsburg statement, wonders if it was written by Schiff, Pelosi or Schumer Top Democrats call for DOJ watchdog to probe Barr over possible 2020 election influence MORE (Calif.), the Democrat likely to lead the House Intelligence Committee during the next Congress, is signaling an interest in interviewing former Attorney General Jeff Sessions Jefferson (Jeff) Beauregard SessionsGOP set to release controversial Biden report Trump's policies on refugees are as simple as ABCs Ocasio-Cortez, Velázquez call for convention to decide Puerto Rico status MORE about the circumstances of his firing.

"On this particular question of what led up to his firing or what information he may have in terms of obstruction to justice, I think that will be of interest to not only our committee but the Judiciary Committee and others as well," Schiff told The Hill in an interview on Thursday. ADVERTISEMENT

Democrats are also increasingly interested in examining the circumstances surrounding 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's appointment of Matthew Whitaker, who has voiced criticism of the federal Russia probe, as a temporary replacement for Sessions.

The Justice Department said on Wednesday that Whitaker would take over oversight of the Russia probe, which was previously overseen by Deputy Attorney General Rod Rosenstein Rod RosensteinDOJ kept investigators from completing probe of Trump ties to Russia: report Five takeaways from final Senate Intel Russia report FBI officials hid copies of Russia probe documents fearing Trump interference: book MORE. Rosenstein, the No. 2 DOJ official, watched over the probe after Sessions recused himself.

In particular, Democrats want to know whether or not Whitaker gave any pledges to the president prior to taking the helm of the DOJ. And Schiff said he also wants to know whether Whitaker told the president he would not step aside from overseeing 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 investigation, like Sessions did.

“I think we certainly need to know whether the acting attorney general, however long he is in that position, was forced to commit to refuse recusal. Whether he has sought the advice of the ethics lawyers at the Justice Department or if he refuses do so, or any others commitments he might have made to the president on the Russia investigation," Schiff said.

Schiff, who currently serves as ranking member of the Intelligence Committee, also expressed concerns about whether the shakeup this week could lead to a structure where the White House received information about the Mueller investigation.

"We also need to make sure that none of the information presented to the attorney general about the investigation was shared with the president," Schiff told The Hill.

Democrats from both chambers have voiced concerns about public comments Whitaker has made while a CNN contributor as well as in op-ed pieces published in The Hill, which scrutinized the Mueller investigation — comments he made before becoming Sessions's chief of staff at the Justice Department.

Already, top Democrats including Senate Minority Leader Charles Schumer (D-N.Y.) and House Minority Leader Nancy Pelosi (D-Calif.) have called on Whitaker to recuse himself for comments he’s made about Mueller.

Schiff echoed these comments Thursday, stating that he is "deeply concerned" by Whitaker's "prejudicial comments" and his ties to "important witnesses" in the investigation, such as former Trump campaign aide Sam Clovis.

Whitaker helped run Clovis's campaign for Iowa state treasurer in 2014. While Clovis has denied to The Washington Post that this should be a disqualifying factor, Schiff said these ties are "cause for recusal."

The DOJ confirmed on Wednesday that Whitaker assumed control of the investigation following his appointment, which the president announced on Twitter not long after a contentious and sprawling press conference earlier that day.

Trump had long bashed Sessions over his recusal in the Russia probe. And after repeated public attacks, Sessions agreed to resign on Wednesday at Trump’s request, according to a copy of his resignation letter obtained by The Hill.

The firing took place one day after the midterm elections in which Democrats won enough seats to take control of the House starting in January.

Democrats have vowed to protect Mueller's investigation, which is examining ties between the Trump campaign and Russia.

And when Mueller brings the investigation to a close, Schiff says the public deserves to know what the special counsel found throughout the course of his investigation.

"I think this is too big an investigation, too big of an important issue, to be swept under the rug. So I would certainly hope that a version of the Mueller report is made public," Schiff said.

"I don’t think the public would stand for the idea that this is too sensitive for them to know or that it can just be presented internally to the Justice Department or even just to Congress… I think the public is going to need to get as full an accounting as possible," he continued.

When pressed whether he would support taking congressional action to push for the public release of the probe's findings, Schiff dodged: "I’m going to reserve judgment, but I can tell you we are not going to allow the president to sweep this under the rug," he said.