Today the Supreme Court has handed down a landmark judgment on the meaning of deprivation of liberty under article 5(1) of the European Convention on Human Rights: see A Reference by the Attorney General for Northern Ireland of a devolution issue under paragraph 34 of Schedule 10 to the Northern Ireland Act 1998 [2026] UKSC 16.
The Supreme Court has taken the rare step of applying the 1966 Practice Statement, and departed from its earlier judgment in Surrey County Council v P; Cheshire West and Chester Council v P [2014] UKSC 19; [2014] AC 896 (“Cheshire West”).
Under the ECtHR case law, an individual is deprived of liberty if three elements are met: (a) the objective element (i.e. the person is confined to a particular restricted space for a material period of time); (b) the subjective element (i.e. where there is no valid consent to that confinement); and (c) if the confinement is imputable to the State (i.e. the state is responsible, either directly or indirectly, for that confinement).
In Cheshire West, a majority of the Supreme Court laid down an “acid test” for determining whether the objective element was met. This established that a person would be confined if they were (a) under continuous supervision and control; and (b) not free to leave. Cheshire West itself was concerned with three individuals: MIG, MEG and P, who were being provided with care and support in a community setting, and who lacked capacity to make relevant decisions about their care and support under domestic law. The Supreme Court held that all three individuals were being deprived of liberty. They were all treated as being confined under limb (a) (i.e. the objective element).The Court also proceeded on the basis that as the individuals lacked capacity under the Mental Capacity Act 2005 to consent to their care or living arrangements, they were unable to provide valid consent under the second limb of the ECtHR test (the subjective element). After Cheshire West, approximately 400,000 persons “of unsound mind” were treated as being deprived of liberty in England and Wales per year.
In a unanimous judgment, the Supreme Court has now held, applying the 1966 Practice Statement, that that decision of the majority in Cheshire West was wrong. The ECtHR did not support the existence of an “acid test”, and instead applied a multi-factorial assessment, taking into account a whole range of factors, including the type, duration, effect and manner of implementation of the measure in question.
The case arose from a decision of the Attorney General of Northern Ireland (“AGNI”) to issue a Code of Practice, which provided guidance on the application of section 306(1) of the Mental Capacity Act (Northern Ireland) 2016 (“the MCA 2016”), which directly linked the concept of deprivation of liberty in domestic law, with article 5 of the Convention. The AGNI had referred a question to the Supreme Court as to whether the Code accurately stated the law in relation to the subjective element (concerning lack of valid consent to confinement) in Article 5. The AGNI argued that persons who lack capacity to take the relevant decision under domestic law, could still provide valid consent to a confinement under article 5.
The Secretary of State for Health and Social Care intervened in the reference to argue that the Supreme Court should not only determine the proper application of the subjective element of a deprivation of liberty, but must also look at the objective element, and that the ECtHR had never adopted an acid test.
The Supreme Court accepted the Secretary of State’s submissions. It held that “in setting out the acid test, the majority decision in Cheshire West departed from the longstanding multifactorial approach to determining whether a person is deprived of liberty within the meaning of article 5 and is wrong” (§53(vi)). The Supreme Court also accepted the AGNI’s submissions on valid consent.
The judgment contains a detailed analysis of the correct approach to identifying a deprivation of liberty under article 5. It will have significant implications for local authorities, ICBs and local health boards, hospitals and care homes, as well as for community settings and the circa 400,000 people currently being treated as though they are deprived of their liberty.
Joanne Clement KC and Zoe Gannon acted for the Secretary of State for Health and Social Care.
The judgment is available here.
Joanne Cement KC, Zoe Gannon and Tim Spencer-Lane (DHSC) will be holding a webinar on the implications of this judgment on 8 June 2026 at 10.00am. If you would like to attend please contact RSVP@11kbw.com.
