Career
Percy first became active in politics as a high-school student in 1965, helping organize demonstrations against the Vietnam War. In 1969, Percy was elected to the initial five-member secretariat of the Vietnam Moratorium Campaign in Sydney. He became the League"s Organisation Secretary in 1972 and its National Secretary in 1973.
Due to the influence of the United States Socialist Workers Party, the SWL later took the name Socialist Workers Party, and Percy continued as secretary.
The SWP later became the Democratic Socialist Party. Percy was central to the Digital signal processing becoming an Australia-wide party during the 1970s.
In the 1980s, he oversaw a series of attempts by the party to reach out to new forces and to regroup with other far-left organisations. He died of cancer on 12 October 1992, at the age of forty-three.