Alexander Butterfield, the aide to former President Richard Nixon who revealed a secret taping system that proved Nixon had been intimately involved in a break-in at the Democratic Party headquarters in 1972 at the Watergate in Washington, D.C., died Monday at age 99. The infamous building is seen ahead of the 50th anniversary of the burglary in 2022. File Photo by Ken Cedeno/UPI | License Photo

March 9 (UPI) — Alexander Butterfield, the aide to former President Richard Nixon who revealed to Congress the secret taping system in the White House that captured recordings about the Watergate burglary, died on Monday at age 99.

Butterfield’s testimony before the Senate Watergate Committee that Nixon had recorded conversations in the White House, and the recordings that were eventually revealed, led to Nixon’s resignation from office over the burglary scandal.

His death was confirmed to several news organizations by his wife, Kim.

Butterfield, who was the head of the Federal Aviation Administration when he was called to testify before the committee, at least partially about rumors that there could be recordings of conversations that included Nixon discussing the 1972 break-in at Democratic Party headquarters in the Watergate building in Washington, D.C.

In his testimony, both during a preliminary interview and in a hearing, Butterfield acknowledged that he’d overseen the installation of a secret recording system in the White House — including the Oval Office and the Cabinet Room — Nixon’s office in the Executive Office Building and at Camp David.

The voice-activated system recorded thousands of hours of talks with aids, officials, members of Congress and others, with only White House Chief of Staff H.R. Haldeman, one of Haldeman’s assistants and the Secret Service, in addition to Butterfield, aware of its existence.

“He had the heavy responsibility of revealing something he was sworn to secrecy on, which is the installation of the Nixon taping system,” John Dean, White House counsel to Nixon during the scandal, said of Butterfield’s revelations.

The testimony, and recordings, revealed how involved with the Watergate break-in Nixon had been and led directly to Nixon’s resignation in 1974 in order to avoid being impeached and removed from office.

Butterfield is survived by his wife, Kim, two daughters, eight grandchildren and 13 great-grandchildren.