Updated at 10:15 a.m. ET

The House Republican Conference voted Monday night to approve a change to House rules to weaken the independence of the Office of Congressional Ethics and place it under the oversight of the House Ethics Committee, a panel controlled by party leaders.

It will be part of a broader House Rules package to be voted on by the full body on Tuesday after the 115th Congress officially convenes and the House elects a speaker.

The Office of Congressional Ethics was established in 2008 under House Democrats, in response to the era of lobbying scandals made notable by Jack Abramoff, the former lobbyist who went to prison on corruption charges.

It is the first independent body to have an oversight role in House ethics. There is no Senate counterpart. The OCE independently reviews allegations of misconduct against House members and staff, and if deemed appropriate refers them to the House Ethics Committee for review. The OCE cannot independently punish lawmakers for any ethics violations.

House Speaker Paul Ryan spoke out against the move, according to a source in the room who said Ryan stated that "there's a bipartisan way to better reform the office."

President-elect Donald Trump was critical of the vote, tweeting Tuesday morning, "With all that Congress has to work on, do they really have to make the weakening of the Independent Ethics Watchdog, as unfair as it may be, their number one act and priority."

Trump senior adviser Kellyanne Conway had defended the move earlier, telling ABC's Good Morning America that the election justified the action by congressional Republicans. "There's a mandate there for them to make significant change," Conway said.

The vote has caused a backlash among Democrats, who say it's hypocritical given that Trump was elected vowing to "drain the swamp" in Washington.

The language approved Monday night, authored by Rep. Bob Goodlatte, R-Va., would prevent staff from making public statements independent of the House Ethics Committee and prevents it from investigating anonymous tips. A senior GOP aide said that's all "because members are sick of having their name dragged through the mud based on partisan sometimes anonymous accusations."

House Minority Leader Nancy Pelosi, D-Calif., who was speaker when the OCE was created, criticized the decision in a statement.

"Republicans claim they want to 'drain the swamp,' but the night before the new Congress gets sworn in, the House GOP has eliminated the only independent ethics oversight of their actions," she wrote. "Evidently, ethics are the first casualty of the new Republican Congress."

In a statement, Goodlatte said his rules change would "strengthen" the OCE and improve due process rights for those subject to ethical investigations.

"The amendment builds upon and strengthens the existing Office of Congressional Ethics by maintaining its primary area of focus of accepting and reviewing complaints from the public and referring them, if appropriate, to the Committee on Ethics. It also improves upon due process rights for individuals under investigation, as well as witnesses called to testify. The OCE has a serious and important role in the House, and this amendment does nothing to impede their work," Goodlatte wrote.

The Goodlatte amendment still would allow the OCE to accept and review complaints, but it would bar the consideration of anonymous complaints. It also would rename it the "Office of Congressional Complaint Review."

While Speaker Ryan spoke out against the move to his fellow GOP lawmakers, his office defended the amendment, saying it provides "greater due process rights, clear timelines for consideration of complaints, and a basic level of oversight by the evenly-split bipartisan ethics committee. It does NOT remove the responsibility of the office to review complaints, carry out investigations, and make referrals to the ethics committee. The office will continue to operate in the new year and provide public accountability to Congress."

In November, Ryan stopped the House from bringing back earmarks — provisions that in the past allowed members to direct spending to specific projects.

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