Colonel Jack Finney was an American military officer.
When flying saucers buzzed White Sands in 1957, Finney ordered the activation of an experimental radar array to track them. This caused interference in the ships' gravimetric drives, and one of them crashed. The Master, in his guise of Major Kreer, ordered the wreckage sent to Corman Air Force Base.
Later, when the Seventh Doctor and his companions were arrested for investigating what had happened, the Doctor contacted the head of the CIA, Allen Dulles. Owing the Time Lord a favour, Dulles told Finney to fully cooperate and provide any assistance necessary to the Doctor. (PROSE: First Frontier)