Speaker of the House Paul D. Ryan (R-Wis.) speaks during a news conference after the weekly House Republican caucus meeting. (Michael Reynolds/European Pressphoto Agency)

In early January, House Republicans’ effort to weaken an independent ethics monitor was thought to have failed after then-President-elect Donald Trump intervened with a pair of tweets questioning the GOP’s priorities and timing.

But in fact, one change to the Office of Congressional Ethics (OCE) slipped through shortly afterward at the behest of Speaker Paul D. Ryan (R-Wis.), little noticed by anyone but the OCE itself and good-government groups that fear it could undermine the office’s work.

The change relates to how new members are chosen for the OCE’s board, which authorizes its investigations. Under the final rules package adopted Jan. 3, the speaker and minority leader no longer must agree on their respective appointments to the board — they merely have to notify each other before proceeding with their own selections.

This subtle change — requiring the two parties to “consult” on new board members instead of “concur” — is raising concerns among accountability and ethics organizations, which say it could make the OCE more vulnerable to partisanship and, in the process, weaken its investigations of misconduct by lawmakers.

“Ethics in Congress has been done with an intentionally bipartisan approach,” said Meredith McGehee, the policy chief at Issue One, a group pushing for revisions to campaign-finance law, and a leading expert on congressional ethics. “This is a stark reversal of that approach. . . . It upsets the fundamental balance that has been key to fighting against the tendency for ethics issues to become partisan.”

Lisa Gilbert, director of Public Citizen’s Congress Watch division, said the appearance of partisanship within the OCE would threaten its credibility.

“How people view an ethics body like this matters,” she said.

GOP aides said Ryan decided to pursue the rules change after Democrats rejected two proposed board members, including former congressman Doc Hastings (R-Wash.), whom Ryan made Republican chairman of the board last month under the new rules.

Hastings chaired the Ethics Committee in 2005 and 2006, drawing criticism from accountability groups for what was seen as the panel’s lack of activity.

“It’s a national embarrassment,” Melanie Sloan, then the executive director of Citizens for Responsibility and Ethics in Washington (CREW), told The Washington Post one year into Hastings’s tenure.

Democratic aides said Hastings and another candidate disqualified themselves by engaging in hyper-partisan behavior while serving on the Ethics Committee.

A spokeswoman for Ryan defended the rules change as a necessary move in the face of Democratic defiance to GOP attempts to fill a vacancy on the board.

“After inexplicable continued obstruction of multiple highly qualified candidates, we were left with no other option to make a rule change in order for the OCE board to operate as intended,” AshLee Strong wrote in an email.

House Democrats created the OCE in 2008 in response to the Jack Abramoff lobbying scandal, designing it as an independent, politically neutral body intended to be more aggressive than the House Ethics Committee, which has been criticized as having a tendency to protect lawmakers by punishing them in only the severest cases of rule-breaking.

The office’s board must authorize each stage of an OCE investigation, including any decision to refer a probe to the House Ethics Committee for further proceedings. Even if the Ethics Committee does not take further action, the OCE is permitted to release a public report of its findings.

The board has six members and two alternates, with each party choosing three members and one alternate. Members are not term-limited, and new members are selected only when a departure creates a vacancy.

In the past, the speaker and minority leader would trade lists of candidates and veto picks by the other they considered unacceptable.

House Minority Leader Nancy Pelosi (D-Calif.), who oversaw the creation of the OCE in 2008 as speaker of the House, defended the original appointment process through a spokesman.

“Since the OCE began its deliberations in 2008, this process has achieved its purpose — there has been little, if any, criticism that OCE was conducting partisan investigations,” deputy chief of staff Drew Hammill wrote in an email. “Leader Pelosi is concerned that the new method chosen by the Republican majority to make these important appointments will lead to the perception that non-partisanship, essential to the mission of the OCE, is no longer important.”

A spokeswoman for the OCE, Kelly Brewington, declined to comment for this article.

Watchdog groups said Hastings’s approach as chair will provide the first clue as to whether the OCE is changing.

“We are hopeful that he will be just as committed to an effective OCE as past members and chairs have been,” CREW Executive Director Noah Bookbinder said. “We are watching very closely and will be very vocal if we see signs that is not happening.”

Members of both parties have criticized and sought to weaken the OCE since its creation.

On Jan. 2, House Republicans approved a measure from Judiciary Committee Chairman Bob Goodlatte (R-Va.) making major changes to the office, including putting it under the oversight of the Ethics Committee, depriving it of a spokesperson and preventing it from investigating anonymous tips.

The vote provoked a national backlash — a tweet from Trump helped prompt the GOP to reverse course — and Republicans abandoned Goodlatte’s plan the next day. This was celebrated as a victory for ethics enforcement, but accountability groups view the final result as a mixed blessing.

People familiar with previous drafts of the rules package said the change to the OCE board appointments process was included before Goodlatte’s broader plan to weaken the office.

“Thousands of Americans mobilized when they saw what was being done to the Office of Congressional Ethics, and while we were collectively able to reverse some of the key changes, this one was kind of under the radar,” said Aaron Scherb, director of legislative affairs for Common Cause.

The first head of the OCE, Leo Wise, said it is crucial to preserve the spirit of nonpartisanship that has defined the board since its inception.

“There has to be a sort of wait and see if that changes,” he said. “I don’t know how much the rule requiring the two leaders to agree on their appointments fostered that, or if it was the commitment of the board members to act in a bipartisan way. That, to me, was the most important thing.”