Marist College Ashgrove 1952 -1958.
Served as Senior Judge Administrator, Supreme Court of Queensland (1991–2007).
President, Industrial Court of Queensland (1986–1993).
Judge, Commercial Causes "B" List, Supreme Court of Queensland (1985–1990).
Judge, Supreme Court of Queensland (1984–1991).
Awarded the Centenary Medal in 2001 and appointed an Officer of the Order of Australia in 2002.
Served as Chairperson and CEO of the Queensland Crime and Misconduct Commission in 2010-2011.
Justice Moynihan’s judgment in the Mabo case as a Queensland Supreme Court Judge gathered crucial local information to the Murray Islander’s case of native title and was key to the High Court decision in 1992 that led to the Native Title Act (1993) which created a framework that recognises Aboriginal and Torres Strait Islander peoples have rights and interests in certain land because of their traditional laws and customs.
Justice Moynihan’s 2008 Review of the civil and criminal justice system in Queensland report led to the Civil Criminal Jurisdiction Reform and Modernisation Amendment Act 2010 which contains the first stages of the Queensland government’s response to the report.