The Mental Health Act 1983 (amended 2007) is tested in virtually every MRCPsych Paper B sitting. Questions are precise — they test specific sections, durations, grounds, signatories, and appeal mechanisms. Clinical approximation is not enough; you need the exact legal framework.
Civil sections
Section 2 — Admission for assessment. Duration: up to 28 days. Grounds: the patient is suffering from a mental disorder of a nature or degree that warrants detention for assessment, and detention is in the interests of the patient's health or safety, or for the protection of others. Requires: an application by an AMHP (Approved Mental Health Professional) or the nearest relative, supported by two medical recommendations (one from a Section 12 approved doctor). The patient can appeal to the Mental Health Tribunal within the first 14 days.
Section 3 — Admission for treatment. Duration: up to 6 months, renewable. Grounds: the patient is suffering from a mental disorder of a nature or degree that makes treatment in hospital appropriate, treatment is necessary for the health or safety of the patient or the protection of others, and appropriate treatment is available. Requires: the same application and medical recommendation structure as Section 2. The patient can appeal to the Tribunal once in each period of detention. The nearest relative can discharge the patient (subject to the responsible clinician's barring order under Section 25).
Section 4 — Emergency admission for assessment. Duration: up to 72 hours. Grounds: the same as Section 2 but where the urgency of the situation means waiting for two medical recommendations is impractical. Requires: one medical recommendation (ideally from a doctor who knows the patient) and an application by an AMHP or nearest relative. Section 4 should be converted to Section 2 as soon as the second medical recommendation is obtained.
Holding powers
Section 5(2) — Doctor's holding power. Duration: up to 72 hours. Allows the registered medical practitioner or approved clinician in charge of a voluntary inpatient's care to detain the patient for assessment. Only applies to patients already admitted voluntarily. The purpose is to hold the patient while a formal Section 2 or 3 assessment is arranged.
Section 5(4) — Nurse's holding power. Duration: up to 6 hours. Allows a registered mental health nurse or registered learning disability nurse to detain a voluntary inpatient if it appears that the patient is suffering from mental disorder to such a degree that it is necessary for the patient's health or safety or the protection of others for the patient to be immediately restrained, and it is not practicable to secure the immediate attendance of a doctor. This is a bridge to Section 5(2).
Police powers
Section 135 — Warrant to search for and remove patients. An AMHP applies to a magistrate for a warrant authorising a police officer to enter premises (by force if necessary) and remove a person believed to be suffering from mental disorder to a place of safety. Duration: up to 24 hours (reduced from 72 hours by the 2017 Policing and Crime Act) with a possible 12-hour extension.
Section 136 — Removal of mentally disordered persons from public places. A police officer who finds a person in a place to which the public has access who appears to be suffering from mental disorder and to be in immediate need of care or control may remove that person to a place of safety. Duration: up to 24 hours with a possible 12-hour extension. The place of safety should be a health-based setting, not a police station, except in exceptional circumstances.
Community Treatment Orders
Section 17A — CTO. Allows a detained patient (under Section 3 or equivalent) to be discharged from hospital subject to conditions, with the power of recall if the conditions are breached or the patient's mental health deteriorates. The CTO lasts up to 6 months initially, renewable. The patient must be recalled to hospital for the CTO to be revoked and detention under Section 3 resumed.
CTOs are controversial and frequently examined. Know the conditions that can be attached, the grounds for recall, and the distinction between recall and revocation.
The nearest relative
The nearest relative is defined by a hierarchy in Section 26 of the MHA — spouse or civil partner, then cohabitant of more than 6 months, then eldest child, then parent, then eldest sibling, and so on. The nearest relative has the power to apply for Section 2 or 3, to discharge the patient from Section 2 or 3 (subject to the clinician's barring order), and to object to Section 3 (an AMHP cannot proceed with a Section 3 application if the nearest relative objects). The County Court can displace the nearest relative if they are unsuitable.
Mental Capacity Act distinction
The MHA and the MCA serve different purposes and the exam tests the distinction. The MHA authorises detention and compulsory treatment for mental disorder. The MCA provides a framework for decision-making on behalf of people who lack capacity to make specific decisions. A patient can be detained under the MHA even if they have capacity to refuse treatment — the MHA overrides the right to refuse for the treatment of mental disorder. Conversely, the MCA applies to all decisions (not just mental health) for people who lack capacity.
iatroX's MRCPsych Paper B bank includes MHA and MCA questions tagged for focused practice. Questions cover specific section details, clinical scenarios requiring section selection, and the MHA/MCA interface. All included at £29 per month or £99 per year.