WATCH LIVE: Judiciary Committee hearing on Trump impeachment

Updated at 10:09 a.m. ET

Wednesday opened the beginning of the end to House Democrats' efforts to impeach President Trump.

The House Intelligence Committee completed what it called the fact-finding portion of the impeachment inquiry on Tuesday with the release of a report about the Ukraine affair and the subsequent vote to adopt it.

Then the curtain rose on a new act, one in which House Judiciary Committee Chairman Jerry Nadler, D-N.Y., and his members are deciding on how to proceed based on what their colleagues have uncovered.

The hearing is underway. Watch it live here.

Nadler, his compatriots and their leader, House Speaker Nancy Pelosi, D-Calif., have said that impeachment isn't a foregone conclusion and that it depends on the outcome of their process.

Nadler has convened a hearing on Wednesday with a panel of four law professors because, he says, the members of the Judiciary Committee need to get a sense about the historic and legal context of impeachment and whether it may be merited in this case.

"This new phase of the inquiry will look different," said one staffer working on the impeachment inquiry. "With the transmittal of the report to the Judiciary Committee, this hearing will examine the constitutional framework put in place to address presidential misconduct."

To be sure, however, Democrats also are likely to restate, for TV audiences, the findings of the report unveiled on Tuesday by Intelligence Committee Chairman Adam Schiff, D-Calif. This case is as serious as it gets, Democratic staffers said ahead of Nadler's hearing.

"The president abused his power to advance his personal, political interests over our own national security interests," as another staffer said.

Republicans step up their defenses

The Judiciary Committee's ranking member, Doug Collins, R-Ga., and Trump's other Republican defenders have mocked and faulted Democrats' process thus far, calling it unfair and also groundless.

The Intelligence Committee's Republicans, led by Rep. Devin Nunes, R-Calif., released a minority report on Monday defending Trump in the Ukraine matter and accusing Democrats of simple political animus.

The White House, meanwhile, said on Tuesday that Schiff was no better than a "basement blogger" trying to find facts to fit his theories.

House Democrats' New Report: Top Trump Officials Knew Of Ukraine Scheme

Trump Impeachment Inquiry

House Democrats' New Report: Top Trump Officials Knew Of Ukraine Scheme

The administration isn't sending an attorney to take part and Trump's campaign said on Tuesday that Nadler's witnesses are "just left-wing liberals who have been talking about impeachment since President Trump took office."

"With witnesses like these, the Democrats' impeachment hearing will be nothing more than political theater," Trump's campaign said. "It's all part of their transparent attempt to overturn the results of the 2016 election and stop President Trump in 2020."

Collins also already has complained about how headlong and reckless he says Nadler has been moving ahead of Wednesday's session. Collins and Republicans are likely to use it to continue to try to undercut the process and mock what they've called Democrats' patchwork case.

In a fiery press conference Tuesday evening, House Republican leaders slammed Schiff and mocked him for not testifying.

The indictment

House rules give Nadler and the Judiciary Committee the responsibility for assessing what, if any, articles of impeachment to draft against Trump.

Democrats could then use their majority on the panel to advance them to the floor of the full House, where, if a sufficient number of Democrats lent their support, Trump could become just the third sitting president in history to be impeached.

That is the equivalent of an indictment by a grand jury — a statement by the House that it considers there to be enough evidence for Trump to stand trial in the Senate.

Republicans, led by Trump ally Majority Leader Mitch McConnell, R-Ky., control the upper chamber and are expected to acquit the president, permitting him to retain his office.

Nadler and Democrats can see what's ahead for this process the same as anyone. But impeachment is worth doing, they've argued, because it sends a message about what Congress will not tolerate and it forces senators to go on the record defending Trump's actions in the Ukraine affair.

Democrats' dilemma

Impeachment is a quasi-legal but mostly political process. Pelosi, Nadler and their compatriots are balancing this as they decide what kind of case to make against Trump.

Should it be narrowly constructed around the facts of the House Ukraine investigation? Or should it be a broader case that reflects more about what Democrats argue has been improper behavior by Trump?

Given that House Democrats likely cannot remove Trump, the question they must ask themselves is what will do him the most political damage and themselves the least damage, mindful about the election next year.

Pelosi and Nadler may have answered these questions already for themselves, but the public aspect of that process, at least, is what is underway on Wednesday.

The hearing also marks Nadler's return to the spotlight after months in center stage for Schiff and the House Intelligence Committee. But Nadler was an early convert on impeachment and insisted earlier this year that his committee was pursuing an impeachment case even before the imprimatur given by the vote of most other Democrats in November.

In that earlier phase, Nadler sought to exploit some of the findings of former Justice Department special counsel Robert Mueller, including those that Democrats have said amount to obstruction of justice by Trump.

The chairman's interest in that thread, which also has involved litigation by the House against Trump and the Justice Department involving evidence from Mueller and other matters, may mean the question isn't settled as to whether Nadler might favor a broad indictment of Trump that takes elements from the Russia investigation — or focuses closely on Schiff's report.

NPR congressional reporter Claudia Grisales contributed to this report.