Rep. Jason Chaffetz, the chair of the House Committee on Oversight and Government Reform, hasn’t offered even mild criticism of President-elect Donald Trump’s many conflicts of interest. But he’s plenty upset with the federal government’s top ethics watchdog, who called out Trump in an unusually public and critical speech on Wednesday.

Chaffetz has summoned Walter Shaub, the director of the Office of Government Ethics, to the Hill for a closed-door interview, and he’s reminded Shaub that his committee has the power to pull the plug on his agency.

“Your agency’s mission is to provide clear ethics guidance, not engage in public relations,” Chaffetz wrote in a letter to Shaub.

Since Election Day, the OGE has struggled to work with the Trump administration to make sure it’s following ethics rules. Shaub’s growing frustration has spilled out publicly in tweets, in emails released under the Freedom of Information Act, and at a forum on Wednesday, when Shaub called Trump’s plan to step back from his businesses day to day “meaningless from a conflict of interest perspective.”

Chaffetz does have a point that Shaub has been unusually public and vocal about the new administration. But Chaffetz’s main job isn’t to defend the administration from attacks. He’s supposed to serve as a check on the executive branch, particularly holding the presidency accountable — and instead he’s going after a relatively powerless member of the executive branch who is critical of Trump.

The ethics office is trying to hold Trump and his team accountable

The Office of Government Ethics was already in Chaffetz’s sights after it issued a statement in December 2015 taking Hillary Clinton’s side in an ethical controversy about whether she should have disclosed fees paid to the Clinton Foundation for her speeches. Now Shaub, who was a civil servant in the ethics office before President Obama appointed him as director in 2015, has been in the spotlight as the most prominent voice criticizing Trump from within the federal government.

On Wednesday, after Trump announced he would not be giving up ownership of his businesses while in office, Shaub gave a blistering speech that stopped just short of calling the president-elect unpatriotic.

“Every president in modern times has taken the strong medicine of divestiture,” he said, urging Trump to reconsider, work with the ethics office, and change his plan.

The ethics office is independent and nonpartisan, and its job is to prevent conflicts of interest within the executive branch. Federal law requires Cabinet nominees and lower-level officials to take whatever steps necessary to ensure there’s no overlap between their public duties and private investments. But those laws don’t apply to the president and vice president, and emails show that Trump’s team virtually ignored the ethics office in the aftermath of the election while Shaub grew more concerned and frustrated.

So Shaub tried to reach the president-elect another way — on Twitter, in a frenetic string of tweets congratulating Trump for divesting from his businesses (a promise he hadn’t actually made). “I was trying to use the vernacular of the president-elect’s favorite social media platform to encourage him,” Shaub explained on Wednesday.

.@realDonaldTrump OGE is delighted that you've decided to divest your businesses. Right decision! — U.S. OGE (@OfficeGovEthics) November 30, 2016

.@realDonalTrump As we discussed with your counsel, divestiture is the way to resolve these conflicts. — U.S. OGE (@OfficeGovEthics) November 30, 2016

Chaffetz wrote that the tweets, as well as the ethics office’s decision to weigh in in favor of Clinton in the speaking fees controversy, suggest the office is overstepping. (He didn’t mention the speech on Wednesday.)

The letter is the second time in two weeks that House Republicans have been skeptical of an independent watchdog’s ability to speak directly to the public. They made a foiled attempt on the first day of Congress to defang the Office of Congressional Ethics, which investigates unethical behavior in Congress. One of the provisions would have banned the office from employing a spokesperson.

Instead of investigating Trump, Congress is threatening its critics

Chaffetz’s letter included a line that concealed a veiled threat in legislative jargon: “OGE’s statutory authorization lapsed at the end of fiscal year 2007 and the Committee has jurisdiction in the House of Representatives for reauthorizing the office.”

In plain English: That’s a nice ethics office you’ve got there; would be a shame if something happened to it.

The law giving the ethics office its power technically expired in 2007, but it stays in effect until Congress decides to change it. Chaffetz, who promised to continue the committee’s “examination” of the ethics office, is reminding Shaub that its fate rests in his hands.

Meanwhile, Chaffetz, whose committee has the power to investigate anything it chooses, has promised only to take a “wait and see” approach to Trump’s conflicts of interest.

That sends a strong signal that what the House of Representatives’ most powerful investigator is interested in isn’t the president-elect’s potential for corruption. It’s the actions of the people who are trying to oppose him.