Trevor Olsson was appointed as an acting Judge of the Supreme Court of the Northern Territory in 2004.

Justice Olsson was a Judge of the Supreme Court of South Australia from 1984 – 2001 and is currently an Auxillary Judge of that Court.

Before being appointed to the Supreme Court bench, Justice Olsson was President of the Industrial Court & Commission of South Australia from 1975 – 1984, Deputy President of that Court from 1969 – 1974, Senior Deputy Master of the Supreme Court from 1966 – 1969 and Deputy Master from 1963 – 1966.

Justice Olsson was admitted as a Barrister and Solicitor in 1953.

Justice Olsson has held numerous appointments over the years including President of the Australian Institute of Judicial Administration from 1994 – 1997, Chairman of the Teachers Salaries Board of South Australia from 1969 – 1984 and Chairman of the Childhood Services Council from 1974 – 1981.

Justice Olsson recently was a Member of the Board of Inquiry into the Anglican Church within the diocese of Adelaide.

Justice Olsson was awarded as a Member of the Order of the British Empire in 1962 and an Officer of the Order of Australia in 2003.