Mental health nursing occurs within a legal and ethical framework that presents conflicts between a paternalistic custodial role and an ethical commitment to autonomy. This paper considers the ethical conflict for nurses posed by acting as second health professional at judicial reviews under Section 16 of the Mental Health (Compulsory Treatment and Assessment) Act. Issues of advocacy and paternalism are discussed in light of the conflict between therapeutic and legislated roles. Strategies aimed at protecting the therapeutic relationship are outlined as a response to the current lack of guidelines in this area. Participation in legal processes of committal requires that nurses reflect carefully and critically on the ethical issues raised.