Rep. Justin Amash (R-MI) became the first Republican congressman to accuse President Donald Trump of engaging in “impeachable conduct,” citing findings laid out in special counsel Robert Mueller’s report on now-debunked collusion between the Trump campaign and Russia during the 2016 presidential election.

Often a lone Republican voice in Congress, Amash sent a series of tweets Saturday faulting both President 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. In a summary to Congress, Barr said Team Mueller concluded that the Trump campaign did not collude with Russia. Further, the attorney general stated Mueller did not reach a conclusion on whether President Trump obstructed justice, stating that he and Deputy Attorney General Rod Rosenstein determined that the president had not done so.

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 meets 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.”

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

President 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. The president has repeatedly referred to the investigation as a witch hunt” and has declared “total exoneration” from any wrongdoing.

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 want the House to open impeachment hearings, but House Speaker Nancy Pelosi (D-CA), has resisted, saying impeachment must be bipartisan.

Rep. Rashida Tlaib, (D-MI), a freshman who opened her term by profanely calling for President 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.

You are putting country first, and that is to be commended. We both took an oath to uphold the U.S. Constitution. Please let me know if you are interested signing on to the resolution to begin the investigation into impeachment. https://t.co/f5CT3uB81d — Rashida Tlaib (@RashidaTlaib) May 18, 2019

In contrast, Republican National Committee chairwoman Ronna McDaniel criticized Amash’s remarks, saying that it’s “sad to see Congressman Amash parroting the Democrats’ talking points on Russia.”

“The only people still fixated on the Russia collusion hoax are political foes of President Trump hoping to defeat him in 2020 by any desperate means possible,” added McDaniel. “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.”

Read Amash’s complete thread below:

I offer these conclusions only after having read Mueller’s redacted report carefully and completely, having read or watched pertinent statements and testimony, and having discussed this matter with my staff, who thoroughly reviewed materials and provided me with further analysis. — Justin Amash (@justinamash) May 18, 2019

Barr’s misrepresentations are significant but often subtle, frequently taking the form of sleight-of-hand qualifications or logical fallacies, which he hopes people will not notice. — Justin Amash (@justinamash) May 18, 2019

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. — Justin Amash (@justinamash) May 18, 2019

Impeachment, which is a special form of indictment, does not even require probable cause that a crime (e.g., obstruction of justice) has been committed; it simply requires a finding that an official has engaged in careless, abusive, corrupt, or otherwise dishonorable conduct. — Justin Amash (@justinamash) May 18, 2019

Our system of checks and balances relies on each branch’s jealously guarding its powers and upholding its duties under our Constitution. When loyalty to a political party or to an individual trumps loyalty to the Constitution, the Rule of Law—the foundation of liberty—crumbles. — Justin Amash (@justinamash) May 18, 2019

Few members of Congress even read Mueller’s report; their minds were made up based on partisan affiliation—and it showed, with representatives and senators from both parties issuing definitive statements on the 448-page report’s conclusions within just hours of its release. — Justin Amash (@justinamash) May 18, 2019

America’s institutions depend on officials to uphold both the rules and spirit of our constitutional system even when to do so is personally inconvenient or yields a politically unfavorable outcome. Our Constitution is brilliant and awesome; it deserves a government to match it. — Justin Amash (@justinamash) May 18, 2019

The Associated Press contributed to this report.