Marion has practiced full-time at the independent bar since 2023. In 2025 she was appointed Deputy President (Legal) of the Mental Impairment Review Tribunal.

Between 2018 and 2023 Marion was a policy adviser to the former Attorney General and Minister for Electoral Affairs, Hon. John Quigley, MLA; and Hon. Roger Cook, MLA (then) Deputy Premier; Minister for Health; Minister for Mental Health. Her advisory work for the Ministers spans a range of policy areas including electoral affairs, voluntary assisted dying, palliative care, aged care, mental impairment, disability, guardianship, and administration.

Marion was admitted to practice in Western Australia in 2001 and in Tasmania in 2008. She has appeared as counsel in all courts in Western Australia, the State Administrative Tribunal, the Mental Health Tribunal and the Federal Circuit Court in Tasmania.

She has a unique perspective regarding ethical issues arising in medico-legal contexts, particularly in relation to decision-making capacity, and in 2021 completed a Master of Bioethics.

Areas of Practice:

• Administrative Law

• Appeals & Judicial

• Criminal

• Disability

• Family Law & De Facto