The Trump effect has landed forcefully on Capitol Hill.

Less than two hours after President-elect Donald Trump criticized House Republicans — in a tweet, of course — for trying to gut an ethics investigative unit on the first day of business in the new Congress, those plans lay in shambles in the Republican conference’s meeting room.

The immediate outcome was to keep intact the independent Office of Congressional Ethics — exactly the status quo that House Speaker Paul D. Ryan (R-Wis.) and his leadership team had hoped to protect. That result, however, appeared largely to be the result of Trump’s intervention rather than Ryan’s maneuvering.

There was a broader outcome, too: The unruly Republican caucus that has wreaked havoc in the House for the entirety of Ryan’s tenure fell in line. And there were signs, judging from Tuesday’s drama, that they might continue doing so this year.

House leaders attributed the reversal of the ethics decision to many factors, not the least of which was a rough period of media coverage highlighting how the lawmakers were abandoning Trump’s pledge to “drain the swamp” of Washington of corruption.

(Peter Stevenson/The Washington Post)

But lurking behind it all was the prospect that Trump’s political power, now aimed at Capitol Hill, can instill fear and force action. By aiming his social-media fire hose on fellow Republicans — even as he assembles a Cabinet filled with billionaires and insiders — Trump made clear that he intends to continue giving voice to the anti-establishment outsiders who propelled him through the Republican primaries against much more seasoned politicians and to an electoral-college win against Democrat Hillary Clinton.

[A day of chaos at the Capitol as House GOP backs down on ethics changes]

That may give Trump leverage over those members of the Republican conference who have claimed the “outsider” mantle for the past six years, a period when the most conservative Republicans have gained stature back home by flouting leadership, whether it was John A. Boehner (R-Ohio) as speaker or Ryan for the past 15 months.

These Republicans regularly turned their backs on party leadership and claimed ideological purity in their carefully crafted districts that were bastions of like-minded conservatives. They operated on the assumption that the only likely political penalty was a primary challenge from the right.

Now, their party’s leader wields a Twitter account with 18.5 million followers. As he prepares to enter the Oval Office in little more than two weeks, Trump is far more popular in their districts than they are. He employs as his chief strategist the former leader of Breitbart News, a conservative media outlet that has included among its top targets the skewering of Republicans not deemed suitably conservative.

As a result, the first day of the 115th Congress served as a sort of beta test of how some Republicans will react when Trump sics his media power on them. If the most conservative flank tries to buck Trump on a pricey infrastructure deal, how will they handle the heat from Trump’s Twitter feed? If moderate Republicans try to block his moves on health care, will they withstand the heat if Trump goes to Breitbart to attack them by name?

On Tuesday the answer came fast: Run for cover.

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“With all that Congress has to work on, do they really have to make the weakening of the Independent Ethics Watchdog . . . their number one act and priority,” Trump asked in a pair of tweets just after 10 a.m., adding that there were “so many other things of far greater importance.”

By 11:50 a.m., literally 10 minutes before the constitutionally mandated start of the new Congress, Ryan and House Majority Leader Kevin McCarthy (R-Calif.) called an emergency meeting. Some Republicans piled into the meeting with their children in tow, there to see their mother or father sworn into another term in Congress.

The night before, by a large margin, House Republicans had approved an amendment to their new rules package for the 115th Congress that would have substantially impaled the investigative capabilities of the Office of Congressional Ethics — an independent body that was formed almost a decade ago after a raft of mostly Republican corruption cases landed in federal courthouses.

The OCE, as it is known, was meant to serve as a quasi-grand jury that would handle complaints from the public and tipsters, as well as reviewing media stories of potentially corrupt acts. If there’s a high likelihood an infraction occurred, it gets referred to the House Ethics Committee, which is evenly split between Republicans and Democrats and has full subpoena power and can mete out punishment.

Lawmakers in both parties have seen the OCE as overly zealous at times, and there have been previous calls to rein in the team of former federal prosecutors who have overseen it the past nine years.

But the Monday night massacre of OCE, on a federal holiday, with almost 50 Republicans still not back in Washington, came with little warning or debate. It was an amendment offered by Rep. Bob Goodlatte (R-Va.), the House Judiciary Committee chairman, and Ryan and McCarthy tried to tell their rank and file they would look foolish if they blew up the ethics process in this manner.

The leaders were steamrolled, with Goodlatte winning 119 to 74.

At the same time Tuesday morning that Trump was tweeting his displeasure, Ryan’s office issued a wordy statement that tried to explain what had happened, and McCarthy held a media briefing. Neither could clearly explain what would come next.

Then the leaders brought in the rank and file for another meeting. Many arguments were made about appearances and how the issue was dominating media coverage.

Oh, and someone brought up Trump.

Rep. Charlie Dent (R-Pa.), a recent chairman of the Ethics Committee, said that members of the House GOP leadership mentioned Trump’s opposition to the OCE changes at the brief closed-door meeting in the Capitol basement, giving weight to reversing Monday night’s decision.

“That should be a consideration,” Dent said, explaining how leaders framed the thinking.

Within minutes, lawmakers rolled out of their meeting, having completely reversed course. Nothing would change for the OCE.

Instead, the normally fractious House GOP marched upstairs and displayed the most unity it has shown in the vote for speaker in six years: All but one Republican supported Ryan, who lost 10 Republican votes in his initial vote in October 2015.

“We will deliver,” Ryan told the House in his valedictory speech.

Paul Kane is The Washington Post’s senior congressional correspondent and columnist. His column about the 115th Congress, @PKCapitol, appears throughout the week and on Sundays.

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