Jon Kyl, former Senate Republican whip from Arizona, dies at 84

Jon Kyl, the Arizona Republican who spent nearly three decades in Congress and rose to become the Senate's No. 2 Republican, has died at 84. His family announced the death Thursday, citing complications from a neurological disease, and shared a statement with Arizona's KTAR News, according to Roll Call.

We know that Jon belonged to all of Arizona, a state he loved and explored with vigor, curiosity, and wonder. Serving his state and nation in Congress was a privilege and responsibility he honored and respected. We are grateful for his full and meaningful public life.

The diagnosis became public in December 2025, when Kyl said he was withdrawing from public life. Fox News reported that the neurological disease had resulted in his development of dementia. The Arizona Capitol Times reported that Kyl died Wednesday and that his family announced the death the following day, citing complications from the disease.

Nearly three decades in Congress

Kyl was elected to the U.S. House in 1986 and took office in 1987, representing Arizona's 4th District for four terms. He won an open Senate seat in 1994 following the retirement of Democrat Dennis DeConcini and was sworn in at the start of 1995. He was re-elected twice and left the Senate in January 2013, succeeded by fellow Republican Jeff Flake.

Republicans elected Kyl whip in 2007, and he held the chamber's No. 2 Republican post until he left the Senate in 2013. He took over from Trent Lott, served under Republican leader Mitch McConnell and was succeeded by John Cornyn. As minority whip he helped hold a fractured coalition together after the 2008 elections left Republicans with just 41 senators, Roll Call reported. He had chaired the Republican Policy Committee and then the Republican Conference.

Doug Ducey, then Arizona's governor, appointed Kyl on September 4, 2018, to the seat left vacant by the death of John McCain, his friend and former colleague. Kyl resigned effective December 31, 2018, and Martha McSally was appointed in his place the following January. He voted to confirm Brett Kavanaugh during his months back in the chamber.

Kyl was the first person to return to the Senate by appointment since New Hampshire Republican Norris Cotton in 1975, and he held both of Arizona's Senate seats at different points in his career. He stayed in Washington after leaving Congress in 2013 as counsel at Covington & Burling, where his clients included Facebook, as the company investigated claims of discrimination against right-leaning users, and the conservative Judicial Crisis Network, Roll Call reported.

Water settlements that shaped Arizona

Kyl was central to Arizona water policy, according to the Arizona Capitol Times, which reported he was the principal sponsor of the Arizona Water Settlements Act approved by Congress in 2004. Carl Artman, then the Interior Department's assistant secretary for Indian affairs, later called him the catalyst who brought the stakeholders together and shepherded the agreement through Congress.

Speaking to reporters at the Capitol on Thursday, Flake said Kyl took on the water and public land issues common to Western states. "I think he did nine Indian water settlements during his time, which has allowed the Indian tribes in Arizona to have the water they need and also for the state to grow sustainably," Flake said.

• Principal sponsor of the Arizona Water Settlements Act, approved by Congress in 2004
• The law authorized the Gila River Indian Community water rights settlement
• It amended the Southern Arizona Water Rights Settlement Act involving the Tohono O'odham Nation
• As an attorney for Salt River Project, he helped create Arizona's 1980 Groundwater Management Act

Brenda Burman, general manager of the Central Arizona Project and a former Kyl staffer, described him in a Thursday statement as the driving force behind the 2004 settlements act. "He understood that water is the lifeblood of Arizona communities and his deep commitment to Arizona permanently shaped our state," Burman said. She called him a true statesman who served his state and country with dignity and honor.

Arizona Senate President Warren Petersen, a Gilbert Republican, said in a Thursday statement that Kyl brought credibility, good judgment and a determination to deliver results, whether he was negotiating complex water agreements or helping guide national security policy. Petersen said Kyl earned the respect of people across the political spectrum without compromising his principles.

A conservative record with exceptions

Kyl was one of the Republican Party's preeminent advocates of a large national security posture, Roll Call reported. He pressed for a tough stance on Iran and strongly opposed plans to close the Guantanamo Bay detention facility during the Obama administration. He served as vice chair of the Congressional Commission on the Strategic Posture of the United States, created to help prepare the country for nuclear-armed adversaries. National Journal ranked him the fourth-most conservative senator in 2007.

A key player on immigration, Kyl was willing to break with his party on the issue. As a member of the Judiciary Committee, he drew flak in 2007 for joining Democrats in support of a pathway to legal citizenship for undocumented immigrants.

Kyl also used the chamber's rules against the opposition. He led the opposition that defeated the Comprehensive Nuclear Test-Ban Treaty, which the Senate rejected 48-51 in October 1999. In 2005 Republican aides said he worked behind the scenes against President George W. Bush's nomination of Harriet Miers to the Supreme Court, among conservatives who considered the White House counsel underqualified. Kyl denied it, and Miers withdrew before the Judiciary Committee voted.

A former lawyer, Kyl was at ease in the legislative weeds of a bill, and Roll Call reported that his whipping relied less on personal relationships than on an ability to translate complex policy into a compelling case for a member's support. Lisa Murkowski, the Alaska Republican, said in 2009 that Kyl's manner was neither aggressive nor pushy. "Everyone leaves the room thinking, yeah we can make this work," she said.

Family confirms death from neurological disease

Kyl died at 84, his family said Thursday, of complications from a neurological disease that Roll Call described as unspecified. He was born Jon Llewellyn Kyl on April 25, 1942, in Oakland, Nebraska, and died in Phoenix. He is survived by his wife, Caryll, whom he met at the University of Arizona, their two children and four grandchildren.

Tributes from Arizona and Capitol Hill

Ducey, who appointed Kyl to McCain's seat, wrote on X that Kyl gave Arizona nearly three decades of principled, thoughtful leadership and gave him mentorship and friendship. "I'll miss him deeply. Rest in peace, Senator Kyl," the former governor wrote. Flake, who took over Kyl's Senate seat after the 2012 elections, wrote that Arizona had lost a giant and called Kyl one of the most diligent and effective public servants the state has ever had.

Jon Kyl loved his state of Arizona and was a true legislator's legislator.

Tributes came from across the political spectrum, Roll Call reported, with Arizonans praising his legacy and impact on the state's politics. Democratic Rep. Greg Stanton wrote that Kyl was a serious and principled lawmaker "with a mastery of policy that made him one of the most effective leaders our state has ever sent to Washington."

Flake said he admired Kyl from the start, when Kyl was in the House and Flake was still in Arizona. When Flake ran for office, he said, Kyl told him to make sure his family was aware of what he was doing and involved in it, because they would either resent it or revel in it. Flake said he last spoke with Kyl shortly before the December statement about his diagnosis and called it a wonderful conversation.

TIME magazine named Kyl one of America's Ten Best Senators in 2006 and included him on its list of the 100 most influential people in the world in 2010. The University of Arizona, where he earned a bachelor's degree in 1964 and a law degree two years later, honored him earlier this year after establishing the Kyl Institute for National Security. He was editor-in-chief of the Arizona Law Review as a student.

From Nebraska to the Phoenix Chamber

Kyl grew up in Nebraska and Iowa, the son of John H. Kyl, who was president of the local Chamber of Commerce and later served more than a decade in the U.S. House. Like his father, he was president of the Phoenix Chamber of Commerce when he won the 1986 Republican primary over John Conlon, a former House member trying for a comeback. "Ordinarily, I don't talk about Republicans and Democrats. I talk about ideas," Kyl once said.