Updated at 5:30 p.m. ET
Signaling a widening gap between Democratic leadership and the House Judiciary Committee, the panel will vote this week on whether to install new procedures for its impeachment inquiry and illustrate its intensifying efforts in the probe.
The move — which will culminate in a vote before the committee on Thursday — will allow staff to question witnesses for extended periods and let the panel accept evidence behind closed doors to further protect sources, among other changes.
It also shows the growing divide between progressives pushing for impeachment and moderate Democrats in the House and their leadership, which is largely opposed to any formal action now. Despite House Speaker Nancy Pelosi's public comments supporting the panel's investigation, privately she has told members that the issue is a loser without strong public sentiment.
On Monday, Pelosi downplayed the move, saying the committee's investigation has been ongoing for "a very long time," and expressed support. She also said other legislation is a top priority, such as approving new gun restrictions.
"We are legislating. We're investigating as we have been, and we are litigating. We are taking our information to court," Pelosi said. "That's the path that we are on, and that's the path we'll continue to be on."
Pelosi said she wasn't familiar with comments by the committee's chairman, Rep. Jerrold Nadler, D-N.Y, that the panel was in the midst of formal impeachment proceedings. However, she said that the committee has her support and that it is executing the party's demands.
"It's not a question of signing off on what they have done. It's a question of what we are doing, that they are implementing, and that's a logical thing for a committee to establish a procedure," she said.
Earlier Monday, a Pelosi aide also reiterated that the speaker supported Nadler's investigation and resolution. Also earlier, a Democrat on the committee said she was in support and defended the procedures move.
"I think Speaker Pelosi respects Chairman Nadler's work in the committee, and I think ... for her, the most important thing is for us to have the strongest hand possible against this president, and the American public to have the whole truth," Florida Democratic Rep. Debbie Mucarsel-Powell, a member of the panel, told CNN on Monday. "So this is just another procedural vote as we continue to intensify our investigation."
The procedures change has precedent from previous impeachment probes and will more clearly define where the committee stands on its investigation, Democratic committee aides said in a call with reporters Monday.
It also tees up a busy fall season for the panel, which could issue articles of impeachment by year's end, according to Nadler and committee aides.
Among the plans, former Trump campaign manager Corey Lewandowski is slated to appear before the committee on Tuesday, Sept. 17. Rob Porter, the former White House staff secretary, and Rick Dearborn, a former White House deputy chief of staff, were subpoenaed to appear before the same hearing.
Nadler said in a statement Monday that Trump went to great lengths to obstruct former special counsel Robert Mueller's investigation, which resulted in 37 criminal indictments and seven guilty pleas. It also revealed 10 possible instances in which Trump obstructed justice, Nadler said.
There are additional questions of violations of the emoluments clauses of the Constitution, Nadler added.
"No one is above the law. The unprecedented corruption, coverup, and crimes by the President are under investigation by the Committee as we determine whether to recommend articles of impeachment or other Article 1 remedies," Nadler said in a statement. "The adoption of these additional procedures is the next step in that process and will help ensure our impeachment hearings are informative to Congress and the public, while providing the President with the ability to respond to evidence presented against him. We will not allow Trump's continued obstruction to stop us from delivering the truth to the American people."
Committee members learned the news of the plan in a Friday afternoon phone call. By Monday morning, the committee had released a resolution detailing the new procedures for the Thursday vote.
The resolution says the panel will allow Nadler to designate which hearings are linked to the impeachment probe and allow committee counsel to question witnesses for an additional hour, with 30 minutes divided between Republicans and Democrats. That goes beyond the five minutes allotted to each lawmaker Monday.
In addition, the panel will be able to accept evidence in closed meetings, and Trump's team can respond in writing to evidence and testimony presented to the committee.
"The committee has taken the next step in its investigation of whether to approve articles of impeachment against President Trump," said a Democratic aide to the committee during Monday's call. "It was a busy recess for us. ... It's going to be a busy fall."
For example, there could be hearings covering "startling" new evidence regarding potential violations of the emoluments clause that prohibits self-enrichment, such as a move by Trump to host next year's G-7 summit at his Doral, Fla., resort and Vice President Pence's recent stay at a Trump resort in Ireland, committee aides said.
The developments come on the heels of a majority of House Democrats publicly announcing support for an impeachment inquiry, according to NPR's impeachment tracker, which marks a milestone that was reached during last month's recess.
"The committee has intensified its investigation," a Democratic committee aide said. "The Mueller hearings were an important inflection point, and this is the next step in the process."
There haven't been any formal votes on launching an inquiry or hearings on articles of impeachment, but many Democrats on the panel insist that the committee's investigations amounted to forward movement on the issue — something many are frustrated hasn't happened sooner.
Some Democrats have accused Nadler of contributing to confusion surrounding the inquiry, with the panel telling the courts in filings that it was in the midst of an impeachment inquiry while telling a different story publicly.
During the August recess, Nadler told CNN that the committee was in the midst of formal impeachment proceedings and could vote out articles of impeachment to the House floor by year's end.
For pro-impeachment House Democrats, the rules changes are a procedural and symbolic step in the panel's efforts to show progress despite the fact that its investigations have yielded little new evidence implicating the president.
Outside advocacy groups hoped, to no avail, that the summer recess would increase public pressure on undecided members and top Democratic leaders to advance impeachment.
The debate about what exactly the committee is doing also highlights the growing divide among House Democrats. Pelosi highlighted her concerns in an Aug. 23 caucus call.
"The public isn't there on impeachment. It's your voice and constituency, but give me the leverage I need to make sure that we're ready and it is as strong as it can be," Pelosi said. "The equities we have to weigh are our responsibility to protect and defend the Constitution and to be unifying and not dividing. But if and when we act, people will know he gave us no choice. If he cannot respect the Constitution, we'll have to deal with that. It's about patriotism, not partisanship."
NPR's Tim Mak contributed to this story.