WASHINGTON (NEXSTAR/AP) — A Republican congressman from Michigan on Saturday became the first member of President Donald Trump’s party on Capitol Hill to accuse him of engaging in “impeachable conduct” stemming from special counsel Robert Mueller’s lengthy investigation into Russian meddling in the 2016 presidential election.

But Rep. Justin Amash stopped short of calling on Congress to begin impeachment proceedings against Trump, which many Democrats have been agitating for.

Often a lone GOP voice in Congress, Amash sent a series of tweets Saturday faulting both Trump and Attorney General William Barr over Mueller’s report. Mueller wrapped the investigation and submitted his report to Barr in late March. Barr then released a summary of Mueller’s “principal conclusions” and released a redacted version of the report in April.

Mueller found no criminal conspiracy between Trump’s presidential campaign and Russia, but left open the question of whether Trump acted in ways that were meant to obstruct the investigation. Barr later said there was insufficient evidence to bring obstruction charges against Trump.

Trump, who has compared the investigation to a “witch hunt,” claimed complete exoneration from Mueller’s report.

Amash said he reached four conclusions after carefully reading the redacted version of Mueller’s report, including that “President Trump has engaged in impeachable conduct.”

“Contrary to Barr’s portrayal, Mueller’s report reveals that President Trump engaged in specific actions and a pattern of behavior that meet the threshold for impeachment,” the congressman tweeted. He said the report “identifies multiple examples of conduct satisfying all the elements of obstruction of justice, and undoubtedly any person who is not the president of the United States would be indicted based on such evidence.”

The Justice Department, which Barr leads, operates under guidelines that discourage the indictment of a sitting president.

A representative for Amash did not immediately respond to an email request to speak with the congressman.

“Any member of Congress has the ability to file articles of impeachment at any time if they believe such a charge is warranted. Bill has said publicly that he is not aware of any impeachable offense,” said Brian Patrick, communications director for U.S. Rep. Bill Huizenga, R-Zeeland, in a statement. 

Trump and Republican lawmakers generally view the matter as “case closed,” as Senate Majority Leader Mitch McConnell, R-Ky., recently declared on the floor of the Senate.

Jim Saalfeld, longtime Republican and Kent County Commissioner, told 24 Hour News 8 his reaction to Amash’s comments.

“He’s a Libertarian, he’s not a Republican,” Saalfeld said. “I know he’s talked about running for president as a Libertarian, so I suspect this is nothing more than a media stunt to bring national attention in that regard.”

Saalfeld doesn’t think Amash’s tweets are the same as when Senator Edward Brooke of Massachusetts became the first Republican to call for President Richard Nixon to resign in November 1973. 

“He has run as a Republican for many years but in my opinion, that is a fraud on the citizens of Kent County and frankly, the members of the Republican Party,” Saalfeld said.

State Rep. Jim Lower, R-Cedar Lake, tweeted “this cannot go unchallenged! I support @realDonaldTrump, I support West Michigan values, I support our party’s values and I will have a major announcement regarding MI CD3 this week!” 

Republican National Committee Chairwoman Ronna McDaniel said on Twitter “it’s sad to see Congressman Amash parroting the Democrats’ talking points on Russia.” 

“Voters in Amash’s district strongly support this President, and would rather their Congressman work to support the President’s policies that have brought jobs, increased wages and made life better for Americans,” McDaniel said in a tweet. 

On the other hand, Democrats who control the House are locked in a bitter standoff with the White House as it ignores lawmakers’ requests for the more complete version of Mueller’s report, the underlying evidence and witness testimony. Some Democrats wants the House to open impeachment hearings, but Speaker Nancy Pelosi, D-Calif., has resisted, saying impeachment must be bipartisan.

Rep. Rashida Tlaib, D-Mich., a freshman who opened her term by profanely calling for Trump to be impeached, applauded Amash.

“You are putting country first, and that is to be commended,” Tlaib tweeted. Tlaib is seeking support for a resolution she’s circulating calling on the House to start impeachment proceedings.