On Thursday night, Nadler tweeted that Whitaker "will appear (Friday) morning at 9:30 am", capping a dramatic day-long standoff over whether Whitaker would scrap his appearance entirely over the Democrats' threat to subpoena him.
At the end of the House Judiciary Committee's hearing with acting Attorney General Matthew Whitaker on Friday, Chair Jerry Nadler (D-NY) said that he was not satisfied with Whitaker's responses to certain questions and that he will use a subpoena to obtain those answers if necessary.
"I am here voluntarily, we have agreed to five-minute rounds", Whitaker said.
Thursday's committee vote didn't issue a subpoena but allowed Nadler to do so if Whitaker was uncooperative.
Collins called the hearing a "dog and pony show" and criticized Democrats for disclosing derogatory information about Whitaker's business dealings hours before the hearing.
"In light of that commitment", department spokeswoman Kerri Kupec said in a statement, Whitaker looked forward to come to Capitol Hill and discussing "the great work" carried out by the department.
Nadler went on to repeat his question, and Whitaker ultimately responded: "I have not interfered in any way with the special counsel's investigation".
Nadler mentioned the battle over whether Whitaker would show up, suggesting that since Whitaker showed up there isn't a need to resort to a subpoena - "for now", he added after pausing ever so briefly.
Republicans made clear they viewed the hearing as pointless political grandstanding, especially since Mr Whitaker may have less than a week left as the country's chief law enforcement officer. "If Whitaker was subpoenaed and refused to answer questions at that point, Congress could refer him to the [Justice Department] for Contempt of Congress".
The House Committee approved the subpoena.
"I am not here to be a puppet to repeat terms and words that you say", Mr. Whitaker shot back.
Whitaker is scheduled to testify before the panel on Friday even though his time leading the Justice Department is coming to a close, with the Senate expected this month to confirm President Donald Trump's nominee for attorney general, William Barr. After refusing to answer in a yes or no fashion and questioned whether she had the authority to continue asking questions because her time had expired, Jackson Lee rebuked the acting attorney general. They also know that Trump supporters and many Republican voters will balk if the Democrats are perceived as overreaching, pushy, or bullying.
The blogger said the Democrats on the committee "are trying to redirect nearly every topic back to the Russian Federation investigation, and Whitaker has repeatedly said that he wouldn't answer questions about his private conversations with the president".
House Intelligence Committee Chairman Adam Schiff has also announced a sweeping investigation into Mr Trump's actions as president, and has hired former White House staff members to aid in the probe.
Rep. Doug Collins of Georgia, the top Republican on the committee, attacked the proceedings, calling it "nothing more than a character assassination" and "political theater".
Whitaker has been undertaking significant preparations ahead of the hearing, including conducting briefings with every the Justice Department component and participating in several mock hearings, according to the officials.