The way in which the legal subjectivity of persons with disabilities is understood, which is particularly true for persons with mental disorders, is evolving in the context of the legal institution of incapacitation. First of all, a shift from a substitute decision-making model to a supported decision-making model is suggested. The former involves depriving such persons of their legal (procedural) capacity and placing them under the care or guardianship of others. The latter is to provide them with the appropriate means to access the support they will need in exercising their legal (procedural) capacity. Hence, the legal institution of incapacitation should eventually be abolished and replaced with a new legal instrument of support, which is to be directly based on supportive guardians, representative guardians and legal assistants. The proper protection of the rights of people with mental disorders is obviously possible only within a democratic state of law.