Born and raised in Wellington Brigadier Kevin J. Riordan was attested into the Royal New Zealand Infantry Regiment (Territorial Force) in 1977 and commissioned as 2nd Lieutenant in 1982. Brig Riordan graduated from Victoria University of Wellington with Bachelor of Arts (History) in 1979 and a Bachelor of Laws in 1982. He was admitted as a Barrister and Solicitor of the High Court of New Zealand 1983.
Brig Riordan has been the legal adviser in respect of all major deployments and is the principal adviser to the Chief of Defence Force on legal aspects of counter-terrorism. He served as Liaison Officer with the Multinational Force and Observers in Israel/Egypt 1990- 1991. He has deployed to South East Asia, the Pacific, Bosnia Herzegovina, the Middle East, and East Timor to deal with a wide range of legal issues. He negotiated the multilateral treaty establishing the Truce Monitoring Group for Bougainville, 1997 - 1998. In 2002 he deployed to Afghanistan to take part in an investigation into the assassination of the Afghan Minister of Labour.
Brig Riordan is an adjunct lecturer in international law at Victoria University of Wellington and the author of the Lexis Nexis Laws of New Zealand title Defence: Warfare. Brig Riordan is also a member of the World Justice Project. He has had 25 years of involvement in practice and teaching of Chinese and Japanese martial arts and holds black belts and master titles in four martial arts. He is the Director of Kempo New Zealand.