ALPINE, Utah >> As chairman of the House Oversight and Government Reform Committee, Rep. Jason Chaffetz was a determined investigator of the Obama administration and of Hillary Clinton’s use of a private email server while she was Secretary of State.

But once Donald Trump took office, he became somewhat more muted.

That looked like it was changing this week when reports emerged that former FBI director James Comey had taken notes after Trump privately asked him to end a probe into his former National Security Adviser before firing Comey.

Chaffetz immediately tweeted that he wanted to see the memo when news broke Tuesday night. On Wednesday his committee subpoenaed FBI records, sparking speculation of a showdown with the White House.

On Thursday, Chaffetz announced he was stepping down from Congress, effective June 30.

The Utah Republican had said he intended to leave sometime during this term, but the abrupt departure is yet another step in the on-again, off-again dance between GOP-led congressional oversight committees and the Republican president.

During a Thursday afternoon news conference at his home south of Salt Lake City, Chaffetz said he was sure his other GOP colleagues on the oversight committee would keep the probe going. It was something that would take months or years, he added.

“There are lots of good people who care about these issues and are well-suited to carry out these investigations,” Chaffetz said.

Chaffetz is the second House Republican who is stepping away from a Trump investigation. Rep. Devin Nunes, the chairman of the House Intelligence Agency, had to recuse himself from that investigation after a bizarre incident where he emerged from the White House and seemed to suggest he had evidence backing up Trump’s groundless contention that he had been surveilled by the Obama administration. Republican Rep. K. Michael Conaway is now overseeing that probe.

One possible replacement for Chaffetz on the Oversight Committee is Rep. Trey Gowdy, the former South Carolina prosecutor who chaired the special Benghazi investigative committee and a close Chaffetz friend. On Thursday, the Republican Gowdy released a statement saying he was talking to other members about the chairmanship.

Trump has long complicated Chaffetz’s life. The five-term congressman rescinded his endorsement of Trump last year after recordings surfaced of the reality show star bragging about groping women, only to hastily re-endorse Trump shortly before the FBI announced it was reviving its investigation into Clinton’s emails.

After Trump won the election, Chaffetz became a lightning rod for criticism that Republicans weren’t aggressively policing Trump.

Liberals said that he did not go after the incoming administration with nearly the vigor used against the prior Democratic administration. Constituents booed him at a raucous February town hall, and a novice Democratic candidate raked in hundreds of thousands of dollars in online donations when she announced her longshot challenge to him weeks later.

Last month, Chaffetz stunned the political world by saying he would leave Congress before his current term ends in 2018. But he did not provide a date for his departure until Thursday.

Chaffetz said he hoped to preside over one final hearing on a botched Obama administration “gun-walking” program, in which federal authorities let gun-runners purchase firearms in hopes of disrupting gun smuggling rings.

The former kicker for the Mormon-owned Brigham Young University football team was first elected to the U.S. House of Representatives in 2008. He strolled to four easy re-elections in his heavily Republican district that stretches from towns in the Wasatch Mountains to the Salt Lake suburbs and Provo, the home of BYU. Chaffetz became chairman of the House Oversight Committee in 2015.

He has not ruled out running for another office, such as Utah governor.

Prior to his time in office, he worked in communications for more than a decade and served as campaign manager for former Utah Gov. Jon Huntsman, Jr.

“I kind of had a little bit of a midlife crisis. I turned 50, I’m sleeping on a cot,” Chaffetz said of his life as a congressman in Washington. “The overwhelming driving force is the idea that I just love my family. And a lot of people will never ever believe that, but that is the truth.”