Buoyed by the decisions of a series of witnesses to ignore requests by the Trump Administration not to testify before Congress, House Democratic leaders said Tuesday evening that they would push ahead with their impeachment investigation of President Donald Trump, seeing no need to hold an official vote now to authorize a formal probe.

"They can't defend the President, so they're going to process," said House Speaker Nancy Pelosi in a news conference at the U.S. Capitol.

"There's no requirement that we have a vote," Pelosi pointed out accurately about the rules of the House - though Congress in the past has held such votes to officially launch such an investigation.

"What a SCAM," said Rep. Jody Hice (R-GA), as Republicans complained bitterly about closed door depositions, and their inability to control the narrative about the investigation - a reminder that elections do matter, as Democrats are able to run this probe simply because they won control of the House in 2018.

Democrats emerged from a closed door meeting in no hurry to have a vote on the House floor, as some lawmakers worried that voters would not be able to divine the difference between launching an investigation, and actually casting a vote on impeachment.

Coming out of a closed door meeting, House Democrats were a loose group, not feeling any pressure to force a vote - arguing it would be a meaningless exercise.

"It seems to me that every day they get more information," said Rep. Mike Thompson (D-CA), who said there should be no rush to any vote.

"I don't think it matters at this point," said Rep. Alcee Hastings (D-FL). "An inquiry is ongoing."

There were some Democrats who were still withholding judgment.

"I'm not talking, I'm not saying anything," said Rep. John Lewis (D-GA), who has steadfastly refused to take a position on the impeachment of President Trump.

Republicans denounced the effort.

"They know they cannot win at the ballot box with these out of touch ideas, so they are trying to impeach," said Sen. Thom Tillis (R-NC).

Republicans have focused mainly on the closed door aspect of depositions, arguing they undermine the credibility of the impeachment investigation.

But GOP lawmakers routinely used closed door questioning during their own investigations of the Russian interference in the 2016 elections, and with controversies like Uranium One - where GOP lawmakers interviewed a man who supposedly held bombshell evidence about wrongdoing involving Hillary Clinton.

The Q&A was done in secret; no transcript was ever relased. And the GOP never issued any details of what was said to lawmakers.