Key takeaways
The Supreme Court overturned Cheshire West and rejected the ‘acid test'
It restored a broader, multifactorial approach based on context and intensity.
A person’s wishes, compliance and care setting now matter in the assessment
Lack of capacity does not automatically mean lack of valid consent.
Fewer cases will count as deprivation of liberty, reducing legal processes
This increases professional discretion but risks weaker safeguards and inconsistency.
On 2 June 2026, the Supreme Court handed down judgment in the challenge by the Attorney General for Northern Ireland to what constitutes a ‘Deprivation of Liberty’ under article 5(1) of the ECHR and the definition given to this term in what is widely known as the ‘Cheshire West’ case (Cheshire West).
The background to the challenge and the various arguments made by parties and intervenors is set out in our previous article: Supreme Court may redefine definition of deprivation of liberty | Hill Dickinson
The decision
The Supreme Court has unanimously overruled Cheshire West, deciding that that judgment went beyond the Strasbourg Court’s jurisprudence and departed from the long-standing multifactorial approach to determine when a person is deprived of their liberty. The Supreme Court confirmed that the Judges in Cheshire West erred in their analysis of the Strasbourg Court’s case law as to the meaning of ‘deprivation of liberty’ in article 5 and in the interpretation they gave to that term. The Supreme Court has concluded that ‘the so-called acid test has never been adopted by the European court and is wrong in principle’ and that the ‘Minister would not be acting incompatibly with article 5 in issuing [the] proposed Revised Code of Practice (to replace the existing Deprivation of Liberty Safeguards Code of Practice)’.
In its judgment, the Supreme Court considered the difference between deprivation and restriction of liberty and noted this to be one of degree or intensity, not nature or substance. The Supreme Court noted that it will not be easy to distinguish between the two and that any approach should be practical and realistic.
In explaining their decision, the Supreme Court concluded that the decision in Cheshire West was wrong in six particular respects:
The assessment of whether someone is deprived of their liberty is multifactorial. It is not sufficient by itself to show there is a deprivation of liberty; a whole range of factors including the type, duration, effect and manner of implementation of the measures in question must be taken into account.
It was wrong to conclude that a person’s compliance or lack of objection is never legally relevant to the question of objective confinement. Strasbourg demonstrates there is some overlap between consideration of the objective and subjective elements.
The ‘acid test’ does not take account of the type of setting where an individual receives care and treatment; the normality of the circumstances in which an individual is cared for is a relevant factor in assessing whether there is a deprivation of liberty.
The ‘acid test’ does not take account of the fact an individual might be subject to innate limitations by reason of their own physical or medical condition. It therefore fails to reflect the need for coercion or some externally imposed restrictions that prevents the individual from exercising their fundamental right to physical liberty.
It was wrong to discount the potential relevance of the purpose for which measures of confinement were imposed.
The approach wrongly equates lack of legal capacity with lack of valid consent. If a person lacks legal capacity to make decisions about their care and residence arrangements but nevertheless has a basic level of awareness about those arrangements, which is sufficient to enable them to know and communicate whether they are happy or unhappy with them, then they can be treated as being able to give or withhold valid consent to confinement by an expression of their wishes and feelings.
Reference is made to two types of case that are relevant to the discussion:
‘Catatonic’ individuals, meaning individuals mentally and/or physically incapable; the Supreme Court suggests that those physically incapable cannot be said to be being deprived of their liberty as, by virtue of their physical condition, they do not have control over their body and therefore do not have any physical liberty to exercise.
Unconscious individuals, meaning those temporarily unconscious as a result of physical condition due to injury or disease or because they have been given drugs in the course of being provided medical treatment. In such cases it is relevant to take into account the individual’s potential to regain consciousness and to make an assessment in light of that. The Supreme Court notes that the importance of holding them in one place and preventing them from leaving if they regain consciousness may be important in making the assessment as to whether there is a deprivation of liberty.
In reaching its decision, the Supreme Court considered the significant administrative and resource implications that the Cheshire West decision has given rise to and the wide ramifications across the care sector in the UK since.
What does this mean?
This judgment fundamentally changes what is currently considered to be a deprivation of liberty in a care setting and overturns the ‘acid test’ laid down in Cheshire West. Instead, it introduces concepts such as ‘incapacitous consent’, determining that if a person appears happy with their care arrangements that can constitute valid consent and no deprivation of liberty would arise, having regard to the normality and purpose of the person’s circumstances.
The implications and points that arise for consideration in the aftermath of the judgment, include but are not limited to:
review of COPDOL11 applications currently being prepared or being made
review of policies defining deprivation of liberty processes
review of standard documents for the assessment of those considered as being deprived of their liberty
fewer legal protections for vulnerable individuals being available, ie no RPR, no automatic challenge under s21A
a significant reduction in COPDOL11 court applications
an increased discretion for professionals and the potential for inconsistent application across organisations as to what constitutes a deprivation of liberty
the potential for challenge where it is not agreed someone has provided or demonstrated ‘valid consent’.
The discussion of the impact of this decision will undoubtedly continue and will flesh out other important practical aspects that will require consideration as the decision takes effect. We will continue to keep you updated and provide guidance as this unfolds so watch this space for further details.
We’ll be holding a breakfast briefing on 16 June 2026 with Emma Sutton KC, Sophia Roper KC and Rhys Hadden from Serjeants’ Inn Chambers. Here's the link to sign up to the event.
If you’d like support in understanding how this landmark judgment may affect your organisation, learn more about our Mental Capacity and Mental Health law expertise.
