Justice Dean Mildren was appointed to the Defence Force Discipline Appeal Tribunal as a Member on 25 September 1996. His Honour has been a judge of the Northern Territory Supreme Courts since 1991.

Following graduation from the University of Adelaide, BA LLB in 1966, his Honour undertook Articles of clerkship and was admitted to the South Australian Bar in 1968, the Northern Territory Bar in 1970 and the Western Australian Bar in 1988.

He was appointed Queen's Counsel in 1983. His Honour worked as a solicitor and barrister in private practice and later practised as an in-house counsel and at the independent bar.

His Honour is a life member of the Northern Territory Bar Association and an Adjunct Professor of Law at the Northern Territory University where he lectures part-time in Legal History. He is Chairman of the Northern Territory Council of Law Reporting and a member of the Editorial Board of the "Australian Bar Review".

His Honour joined the Army Reserve as a Legal Officer in 1974 and subsequently became Chief Legal Officer of the 7th Military District. He was appointed a Defence Force Magistrate and member of the Judge Advocates Panel in 1986.