Dr Ellis is a forensic psychiatrist in public and private practice. He holds the post of Clinical Director and Medical Superintendent of The Forensic Hospital in Sydney. The Forensic Hospital is the largest secure hospital for forensic patients in Australasia. He holds a conjoint appointment as Associate Professor with the University of New South Wales Medical Faculty, School of Psychiatry where he is an Academic Program Director for the Master of Forensic Mental Health program. He is a Consulting Psychiatrist to the NSW Police. He is a lecturer for the NSW Health Education and Training Institute. He has a private medico legal and clinical practice.