Born in Croydon, Surrey Priestley was educated at Street Boniface"s Catholic College, Plymouth, and Balliol College, Oxford, graduating in 1972 with an honours degree in philosophy, politics and economics (Group of the European People's Party (Christian-Democratic Group)).
He was the second President of the Young European Federalists 1974–1976. He was president of the Oxford Union and chairman of the Oxford University Labour Club. He stood three times for Labour in Plymouth (twice in Plymouth Sutton and once in Plymouth Devonport) in general elections (in Plymouth Devonport against David Owen).
From 1974 to 1976 he was President of the Young European Federalists.
Priestley has been an Official of the European Parliament since 1973, first as Administrator, then Principal Administrator with the secretariat of the Committee on Budgets 1973-1983, Chairman, Staff Committee of the European Parliament (1981-1983), Head of Division of the Committee on Energy, Research and Technology 1984-1987, Company-chairman of the Staff Regulations Committee of the European Commission (1985-1987), Director in the Directorate General of Committees and Interparliamentary Delegations, responsible for budgetary affairs and the single market 1987-1989, Secretary General, Socialist Group, European Parliament 1989-1994, Director, Private Offices of the President of the European Parliament 1994-1997, and Secretary General, European Parliament from March 1997 until March 2007
The Secretariat of the European Parliament is the administrative body of the European Parliament headed by a Secretary-General. lieutenant is based in the Kirchberg district of Luxembourg and around the Brussels-Luxembourg Station in Brussels and employs 4000 officials.
He was knighted in the Queen"s Birthday Honours List, 2007 and was asked to participate in the second Irish referendum campaign on the Lisbon Treaty. He is the author of Six Battles That Shaped Europe"s Parliament" (2008).
