In a decision that surprised some, longtime U.S. Rep. Doc Hastings said Thursday he’ll retire at the end of the year after 20 years in Congress representing the 4th Congressional District.

“It’s been a great privilege,” said Hastings, a Pasco Republican, in an interview with the Yakima Herald-Republic.

Retirement has been on his mind for several years, said Hastings, 73, adding that his family — wife Claire, three adult children and eight grandchildren — influenced his decision.

“It’s been 20 years. I have to say that my family played a big part of (the decision).”

But he allows it wasn’t easy: “I’ve always said the hardest part of making the decisions is making a decision.”

Hastings, a small businessman before he entered politics full time, was first elected in 1994 when he defeated then-Rep. Jay Inslee of Selah, now Washington’s governor. Over time, his seat became one of the safest in the country as he handily defeated Democratic challengers and never faced a serious threat from far-right elements of the Republican Party.

His announcement surprised a number of those in the Yakima area who were close to him personally and involved politically. It also drew responses from other elected officials across the country, from Olympia to Washington, D.C.

Inslee released a statement on Hastings’ retirement that reflected on the races between the two — Inslee defeated Hastings in his first bid for Congress in 1992 — and wishing the congressman luck in the future.

“I always appreciated Doc’s hard work on behalf of the 4th District. We worked together on the Hanford Caucus that helped keep the issue a priority in Congress,” Inslee said in a prepared statement. “Despite the fact that we each beat the other once, we had a good working relationship, could enjoy a laugh together and swapped plenty of basketball tales.”

House Speaker John Boehner issued a statement calling Hastings “a very dear friend.”

“I’m grateful for Doc’s service to our institution and our nation, and for his friendship and support throughout our many years together in the House,” Boehner said.

In Yakima, Hastings’ former district office manager, Ryan Rodruck, now station manager of local PBS affiliate KYVE, said as a leader Hastings put great trust in his staff to do their jobs for constituents.

“He gave us a lot of leeway and trusted my judgment,” said Rodruck, who worked for Hastings from 2006 to 2013. “We spent a lot of time on the road together and he was always engaged with what was going on in Yakima.”

Yakima County Republicans chairman John Puccinelli said the announcement was news to local party leaders. Puccinelli said Hastings’ service will be missed.

“He worked for the mainstream Republican Party,” he said. “I’m disappointed to see him leave, but sometimes new blood isn’t bad, either.”

Yakima Valley Business Times publisher Bruce Smith, a longtime local Republican fundraiser and campaigner, said Hastings left a permanent legacy in the district.

“Doc started his political career as a foot soldier in the Reagan revolution and is leaving political life as the chairman of a powerful committee in the United States House of Representatives,” Smith said in an email. “That ain’t nothin’.”

Hastings’ foes often characterized him as beholden to special interests and overly partisan, voting in lockstep with the Republican Party leadership.

But elected state Democrats such as U.S. Sen. Patty Murray praised the retiring congressman for his efforts on the Hanford cleanup, among other projects of importance to the district and the state.

“I am particularly grateful to have been able to work with Doc on ensuring the federal government lives up to its responsibility to clean up Hanford,” Murray said in a prepared statement. “I always knew that we had each other’s back over the years when it came time to showing either the new Republican or Democrat in the White House that Hanford cleanup demanded their attention and that we were going to hold them accountable.”

Hastings’ 20 years is twice as long as he pledged to serve. Upon his election, he set his own term limit of 10 years. Other Republicans were behind a limit of six years under the “Contract with America.”

The state’s voters had approved an initiative limiting House members to three terms, but that law was later overturned by U.S. Supreme Court rulings. Hastings subsequently brushed off his original pledge because of the court rulings, and voters didn’t seem to mind.

Hastings did not seek the spotlight in Congress, but it found him when then-House Speaker Dennis Hastert named him chairman of the House Ethics Committee in 2005, not a position Hastings wanted.

Democrats cried foul when Hastings fired the committee’s staff members and tried to name his longtime congressional chief of staff, Ed Cassidy, as the new committee staff director. Cassidy eventually settled for a position as an aide. Critics also accused Hastings of planning to go soft on Tom DeLay, the powerful Republican leader at the time. Hastings staffers let it be known that Hastings had clashed with DeLay and his heavy-handed style.

The controversy swirling around Hastings finally eased when the ranking Democrat on the committee, Rep. Alan Mollohan of West Virginia, resigned his seat under his own ethical cloud. Rep. Howard Berman, a senior California Democrat, replaced Mollohan.

Berman and Hastings developed a good relationship. “If I thought he was someone who had an agenda that was motivated by partisan goals, I would have made that clear,” Berman told the Yakima Herald-Republic in 2007. “But we had a job to do and we subordinated the political and personal to the institutional.”

Together, they led the 2006 investigation of former Rep. Mark Foley, R-Fla., who resigned for sending sexually explicit emails to at least one underage male after the teenager had served as a congressional page.

As a congressman from one of the most conservative districts in the West, if not the country, Hastings reliably attacked Democratic policies and legislation, from the Endangered Speces Act to the Affordable Care Act. He was a relentless critic of now-retired Judge James Redden of the U.S. District Court in Oregon and a Democratic politician before he became a judge.

Redden became the central figure in the conflict between industry interests and environmentalists over dams on the Columbia and Lower Snake rivers, saying the federal government had failed to protect salmon under the Endangered Species Act.

In 2012, Hastings issued some of his harshest words about Redden, who had told a radio reporter after he retired that the lower Snake River dams should be removed.

Said Hastings of Redden’s judicial career: “He issued unprecedented, questionable and expensive rulings resulting in his literally seizing control of the river system’s operation. He ignored clear and sound science that salmon species are returning in numbers greater than before these dams were built, and forced taxpayers to pay for millions of dollars in higher energy bills and lawyers’ fees.”

Although Boehner, and Hastert before him, could count on Hastings to be a loyal foot soldier for the Republican agenda, the congressman stood up for his district many times when his party was not necessarily on board.

In 2003, Hastings persuaded then-Defense Secretary Donald Rumsfeld to change his mind and support legislation that would allow immigrants in the military to be eligible for U.S. citizenship after one year in uniform.

While on the Rules Committee, Hastings persuaded his Republican colleagues to pull a bill that would have cost Washington state nearly $700 million a year by granting an industry tax break. He drew praise from then-U.S. Rep. Norm Dicks of Bremerton for putting the state before his party.

Hastings said he will finish out his term in much the same way he has spent the last 20 years: Fighting for the interests of his conservative district.

Though he has supported comprehensive immigration reform in the past, he said he does not expect the contentious issue to come up before the end of the year.

“I guess the best thing I can be proud of is that I stated what I believe to the voters in Central Washington, and they gave me the privilege 10 times to represent them,” Hastings said.

• Assistant City Editor Leah Beth Ward contributed to this story.