The appointment comes as Turnbull on Wednesday ordered an inquiry into the treatment of children in the Don Dale Youth Detention Centre in Darwin after videos emerged showing prison guards torturing and mocking teenage inmates.
"Mr Martin is eminently qualified to undertake this important role, and will bring to the royal commission a wealth of legal experience… He has a deep understanding of the legal and justice systems of the Northern Territory, and a deep familiarity with issues arising from the engagement of indigenous people with criminal justice," Turnbull said, as cited by The Australian.
Martin, 68, was a judge of the Supreme Court of South Australia before being appointed Chief Justice of the Supreme Court of the Northern Territory in 2004, where he served for six years. In 2012, he also served as an acting Judge of the Supreme Court of Western Australia.
The Don Dale facility became a focus of controversy in 2014, when the tear gas incident occurred several weeks after a number of teenage prisoners attempted an escape and were placed into the prison's isolation wing.