After graduating in Arts (Hons) (1965) and Law (1967) from The University of Melbourne, the Hon David Harper joined the Victorian Bar in 1970, and was appointed Queens Counsel in 1986. He was Chairman of the Victorian Bar Council (1990-1991), and was appointed a Judge of the Supreme Court of Victoria in 1992, becoming a member of the Appeal Division of that Court in 2009. He retired from the Court in June 2013. He was President of the Victorian Association for the Care and Resettlement of Offenders between 1995 and 2012, after which he became - and remains - its patron. He was President of the Victorian Branch of the International Commission of Jurists (1992-1999), President of the Graduate Union of The University of Melbourne (1997-1999), a part-time Commissioner of the Victorian Law Reform Commission (1991-1992 and 2001-2008), and President of the Judicial Conference of Australia (2010-2012). He has chaired the International Humanitarian Law Committee of the Australian Red Cross (Victoria) since 2001.
He became a Member of the Order of Australia in 2008 for service to law reform, the judiciary, international humanitarian law and the community.