WASHINGTON – A key House panel approved Democratic rules Wednesday mapping how public hearings will work in the impeachment investigation of President Donald Trump, after weeks of Republicans criticizing the inquiry for holding closed-door meetings in the basement of the Capitol.

Rules Committee Chairman Jim McGovern, D-Mass., said the resolution sets the rules for public hearings at the Intelligence and Judiciary committees, as the investigation moves into a public phase.

“There is serious evidence that the president may have violated the Constitution," McGovern said. "I don't know how this is going to turn out, but we need a process in place."

But Rep. Tom Cole of Oklahoma, the top Republican on the panel, said the resolution wasn't fair to Trump or to Republicans in Congress because the Intelligence Committee has been conducting closed-door depositions for weeks and might not share all its evidence with the Judiciary Committee.

“In my view, it’s not a fair process, it’s not an open process," Cole said.

The committee approved the resolution on a 9-4 vote. The full House of Representatives is scheduled to vote Thursday on the resolution, which could put moderates in both parties under scrutiny heading into the 2020 election. The floor vote is expected as one in a series beginning about 10:30 a.m. ET.

House Speaker Nancy Pelosi, D-Calif., declared a formal impeachment inquiry Sept. 24. But Trump has called the inquiry a partisan "witch hunt." White House counsel Pat Cipollone notified Pelosi Oct. 8 that the administration wouldn’t cooperate for lack of a full House vote.

The impeachment effort has focused on three panels – Foreign Affairs, Intelligence, and Oversight and Reform – investigating how Trump urged Ukraine to investigate the president's rival, former Vice President Joe Biden, while withholding nearly $400 million in military aid. The Judiciary Committee has investigated possible obstruction of justice, based on episodes described in special counsel Robert Mueller's report on Russian interference in the 2016 election.

Provisions in the resolution allow Intelligence Chairman Adam Schiff, D-Calif., and Rep. Devin Nunes of California, the panel's top Republican, to each question witnesses for up to 90 minutes or delegate their time to staffers before rank-and-file lawmakers each ask questions for five minutes. Republicans on the Intelligence and Judiciary committees could subpoena witnesses and documents, and if the chairman objected, Republicans could ask for a committee vote.

The Intelligence Committee and other panels investigating Trump would provide reports to the Judiciary Committee, which would draft possible articles of impeachment. At Judiciary hearings, the president's counsel would be able to participate by receiving evidence and staff reports, questioning witnesses, submitting additional evidence and being invited to offer a concluding presentation.

But if the administration refuses to make witnesses or documents available to the committees, Judiciary Chairman Jerry Nadler could deny requests from the president's counsel to call or question witnesses.

“This is a serious moment for our nation," Nadler, D-N.Y., said when the resolution was unveiled. "This committee is committed to executing its part of the House’s ongoing impeachment investigation with the highest fealty to the Constitution.”

Cole criticized the resolution for giving the Schiff the authority to reject Republican subpoenas and for giving Nadler the power to limit the president's ability to call or question witnesses.

“That’s a heck of a situation where you get to decide what’s necessary for an investigation," Cole said.

The Democratic resolution wasn't enough to appease concerns among Republicans, who worried about the lack of additional resources for committees participating in the inquiry and that the Intelligence Committee might not pass along all the confidential evidence it has gathered to the Judiciary Committee.

“That’s just wrong," said Rep. Debbie Lesko, R-Ariz. “This is not fair at all."

Rep. Michael Burgess, R-Texas, criticized the process that allowed six committees to investigate Trump, while the president's counsel will participate only in hearings at the Judiciary Committee.

"Really this is nothing more than a fishing expedition," Burgess said.

The White House has denounced the measure in a statement by press secretary Stephanie Grisham, saying the resolution continues the impeachment "scam" without allowing "any due process for the president."

“The Soviet-style process that Speaker Pelosi and Adam Schiff have been conducting behind closed doors for weeks now has been rotten to the core," Rep. Steve Scalise of Louisiana, the second-ranking Republican in the House, said when the resolution was released.