WASHINGTON — Representative David Cicilline, Democrat of Rhode Island and an impeachment manager in the second trial of former President Donald J. Trump, announced Tuesday that he would be leaving Congress in June.
Mr. Cicilline, 61, will become the president and CEO of the Rhode Island Foundation, the state’s largest funder of nonprofit organizations.
In a statement, Mr. Cicilline called the job offer “unexpected” but one he felt he could not turn down.
“It is an extraordinary opportunity to have an even more direct and meaningful impact on the lives of residents of our state,” he said. “The same energy and commitment I brought to elected office, I will now bring as CEO of the Rhode Island Foundation, advancing their mission to ensure all Rhode Islanders can achieve economic security; access quality, affordable health care; and attain the education and training that will set them on a path to prosperity.”
In his seventh term in Congress, Mr. Cicilline is a member of the Foreign Affairs and Judiciary Committees. He is also a member of the Democratic leadership.
He will remain in office until June 1, and his staff will continue to assist constituents until a new member is elected to finish the remainder of the two-year term.
In 2019, as a member of the Judiciary Committee, Mr. Cicilline worked to investigate Mr. Trump during House Democrats’ first impeachment effort. He took on a larger role as an impeachment manager in Mr. Trump’s second trial after a mob of pro-Trump supporters stormed the Capitol complex on Jan. 6, 2021.
“Since his resounding defeat in the presidential election in November, Donald Trump has done everything but concede to the democratic will of the American people,” Mr. Cicilline wrote in a guest essay in The New York Times published ahead of the impeachment trial.
He added: “We cannot let this go unanswered. With each day, Mr. Trump grows more and more desperate. We should not allow him to menace the security of our country for a second longer.”
Mr. Cicilline also led a subcommittee on antitrust, commercial and administrative law. In his work on antitrust law, he oversaw what experts described as among the most serious congressional inquiries into potential anticompetitive corporate behavior in decades, focusing on some of the country’s most powerful tech companies, including Amazon, Google and Facebook.
Before joining Congress, Mr. Cicilline worked as a public defender in Washington and served two terms as the mayor of Providence, R.I., where he was the first openly gay mayor of a U.S. state capital.
Representative Hakeem Jeffries, Democrat of New York and the minority leader, called Mr. Cicilline an “effective and thoughtful legislator” and a “close friend.”
“David has been a leading advocate for L.G.B.T.Q. Americans in the fight for full equality under the law, and he has led House Democrats in our efforts to get weapons of war off of our streets to end the gun violence epidemic once and for all,” he said. “He has been a dedicated defender of our democracy.”
Lisa Gilbert, executive vice president of the progressive group Public Citizen, said in a statement that Mr. Cicilline “will leave behind a substantial and meaningful legacy in Congress — from reinvigorating antitrust policy, to helping to lead the charge for progressive regulatory policy reform, to spearheading landmark anti-discrimination legislation for the L.G.B.T.Q.+ community.”
“He will be sorely missed,” she added.