Mental Health Act 1983
(MHA 1983)
The principal statute governing compulsory detention and treatment for mental disorder in England and Wales. Provides for civil sections (s.2 assessment, s.3 treatment, s.4 emergency, s.5 nurse's holding power), criminal sections (Parts 3), Community Treatment Orders, s.117 aftercare, and Mental Health Tribunal review. Amended significantly in 2007.
The MHA 1983 framework: civil detention (Part 2) for those with a mental disorder posing risks to themselves or others; criminal detention (Part 3) for mentally disordered offenders. Most common sections: s.2 (28 days for assessment), s.3 (6 months renewable for treatment), s.4 (72 hours emergency), s.135 (warrant entry from a private home), s.136 (place of safety from a public place), s.117 (free aftercare after s.3). Mental Health Tribunal review is automatic at first detention; renewal periods give further review rights. The 2025 Mental Health Bill proposes significant reforms.
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Related guides
Mental Health Act 1983 Basics
The Mental Health Act 1983 (MHA 1983), as amended by the Mental Health Act 2007, is the legal framework in England and Wales that allows people with serious mental disorders to be assessed, detained in hospital, and treated without their consent in defined circumstances. Understanding its key provisions is essential for patients, carers, and advocates.
6 min
Section 135 Warrants: Police Entry Powers for Mental Health Assessment
Section 135 of the Mental Health Act 1983 lets a Magistrates' Court grant a warrant authorising the police to enter a private home, remove a person, and take them to a place of safety for mental health assessment. It is a serious power exercised carefully. This guide explains when it is used, the procedure, the person's rights, and how to challenge misuse.
10 min