Former U.S. Senator Jon Kyl, a prominent Republican lawmaker from Arizona known for his influence on water policy in the Western United States and his role in the confirmation of Supreme Court Justice Brett Kavanaugh, has died at the age of 84. He passed away Wednesday night due to complications related to a neurological disorder, according to Gordon James, a close family friend.

Kyl withdrew from public life in December 2025 after revealing he had been diagnosed with dementia. His extensive political career spanned nearly 30 years across both chambers of Congress, beginning during the administration of President Ronald Reagan and continuing through the first term of President Donald Trump.

During his tenure in the Senate, Kyl rose to prominence within his party, serving as the Republican minority whip during his final full term. After retiring from elected office in 2013, Kyl transitioned to work as a lobbyist. However, he briefly returned to the Senate in 2018 when Arizona Governor Doug Ducey appointed him to fill the vacancy created by the death of Senator John McCain.

Kyl was widely respected for his leadership on issues critical to the West, notably his involvement in shaping key water legislation that affected resource management across several states. His career reflected significant political shifts within the Republican Party over several decades.