The UN Convention on the Rights of Persons with Disabilities (CRPD) is a major milestone in safeguarding the rights of persons with disabilities. However, the General Comment on Article 12 of the CRPD threatens to undermine critical rights for persons with mental disabilities, including the enjoyment of the highest attainable standard of health, access to justice, the right to liberty, and the right to life. Stigma and discrimination might also increase. Much hinges on the Committee on the Rights of Persons with Disabilities' view that all persons have legal capacity at all times irrespective of mental status, and hence involuntary admission and treatment, substitute decision-making, and diversion from the criminal justice system are deemed indefensible. The General Comment requires urgent consideration with the full participation of practitioners and a broad range of user and family groups.