Andrew Boyle, 71, author and former broadcast news exec whose book “The Climate Of Treason” led to the public unmasking in 1979 of British art expert Anthony Blunt as a onetime Soviet double agent, died April 22 in London, cause unreported.

Though it did not actually name Blunt as the fourth man in the notorious Philby-Burgess- Maclean spy ring, the book provoked pressure from lawmakers that led to disclosure of Blunt’s treason by then Prime Minister Margaret Thatcher. Blunt had been granted immunity from prosecution after confessing to his role 15 years earlier.

Born in Dundee, Scotland, Boyle was a British intelligence officer in World War II before joining the BBC, where he was a scriptwriter and then a news editor and producer. He was credited with several news programming innovations, and later became head of news and pubaffairs for BBC’s Scottish region.

He published several biographies, including one of John Reith, the BBC’s first chief executive and the architect of its public broadcasting ethos.

Survived by his wife, son and a daughter.

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