Kent was born in Nowchwang, Manchuria where his father was the American Consul. He was educated at a prestigious private school, St. Albans School in Washington, DC, followed by Princeton University where he studied history. Through his father's connections he joined the Diplomatic Service and was posted to Moscow. By 1939 he was under suspicion for espionage for the Soviet Union, but lacking any solid evidence, the Diplomatic Service decided to act by transferring him to the London Embassy shortly after the outbreak of World War II.
With a position which required him to encode and decode sensitive telegrams, Kent had access to a wide range of secret documents. He began to take many of the more interesting ones home with him. Meanwhile, he was also becoming active in politics. Kent's views are uncertain but many have assumed that he took an isolationist line, and that he was prepared to help British anti-war campaigns. Early in 1940, through Anna Wolkoff, he met Archibald Maule Ramsay, an anti-semitic Conservative Member of Parliament, and joined Ramsay's group "The Right Club". Ramsay gave him the Right Club's membership list for safe-keeping.
Kent's abstraction of documents had been noticed and on May 20 he was arrested in a dawn raid at his flat (1,500 documents were found there). Ambassador Joseph P. Kennedy, Sr. agreed to waive diplomatic immunity and Kent was tried in camera under the Official Secrets Act 1911. On November 7, 1940 he was convicted and sentenced to seven years' imprisonment. The trial and imprisonment of Kent, and the co-operation of the US authorities, led isolationist groups in the USA to claim that he had been framed and that the trial was an attempted cover-up of an attempt to get the USA to join the war.
At the end of the war Kent was released and deported to the USA. He there insisted that he had always been a staunch anti-communist, but was nevertheless interrogated by the FBI in 1951, where he told no more than had been disclosed at his trial. The FBI investigation has been criticised as naive. Afterwards, Kent was associated with newspapers linked to the Ku Klux Klan. He died in poverty in Texas in 1988.
- Ray Bearse and Anthony Read, Conspirator: The Untold Story of Tyler Kent (New York: Doubleday, 1991).