Kirby served as one of the seven Justices of the High Court of Australia, Australia's highest constitutional and general appellate court from 1996-2009. Former Justice Kirby was appointed to the original Global Commission on AIDS of the World Health Organization. He has served on numerous Expert Groups of UNAIDS. Presently, he serves as a Member of the Global Panel of UNAIDS on AIDS and Human Rights. He is also a member of the Board of Governors of the Kinsey Institute for Research in Sex, Gender and Reproduction within Indiana University.