By Matthew Evans and Eleanor Sibley, 7th December 2025
On 20-22 October 2025, the Supreme Court heard a Reference by the Attorney General (AG) for Northern Ireland asking it to re-consider its judgment in Cheshire West.
Its decision, made in the absence of a concrete factual matrix, will have far-reaching and very concrete consequences.
The AIRE Centre is a specialist human rights legal charity, which uses the power of European law to protect individual and collective fundamental rights [The AIRE Centre]. The AIRE Centre intervened in Cheshire West and applied to intervene in the AG’s Reference but was refused permission.
In this blog post, we consider the background to the Reference and some of the principles of European and international law that we hoped to put before the Court.
The AG’s Reference
The subject of the AG for Northern Ireland’s reference was the subjective element of the test for a deprivation of liberty under Article 5 ECHR.
This is one of three parts to the test:
- The objective element of being confined in a restricted place for a not negligible length of time (this was the primary focus of the appeal in Cheshire West;)
- The subjective element – a lack of valid consent; and
- Attributability to the state.
In Cheshire West the subjective element of the test was not in issue. However, the Supreme Court made some observations on it. Based on those observations, it appears to have assumed that if a person lacks mental capacity to consent to an objective confinement, then there can be no valid consent for the purposes of the subjective limb.
It was this assumption that the AG for Northern Ireland asked the Supreme Court to reconsider. She argued that even when a person lacks mental capacity to consent to confinement, valid consent may be given through the expression of wishes and feelings going beyond mere acquiescence.
By the time of the hearing in October 2025, the case had taken on a life of its own, and the Supreme Court heard submissions on whether it should revisit its judgment in Cheshire West in its entirety.
The central issues to be resolved by the court are ones of legal principle, given there is no protected party or concrete factual matrix to consider in this case. Nonetheless, they will have important consequences.
The background to the Reference
The background to this issue is long and complex, but we should start with what Cheshire West decided.
The Supreme Court was primarily concerned with the objective limb of the test for a deprivation of liberty. It sets out what has been described as an ‘acid test’ according to which people who are under continuous supervision and control and not free to leave are subject to objective confinement. The Supreme Court found that this is so even if they seem content or unaware of it. and even if their living arrangements are comfortable and make their life as enjoyable as it could be – memorably described by Lady Hale in her judgment, as a ‘gilded cage is still a cage.’ Lady Hale’s view was that what it means to be deprived of one’s liberty must be the same for everyone, whether disabled or not. [46]
Based on the court’s observations on the subjective limb, it has been widely assumed that where the ‘acid test’ is met, and the confined person lacks mental capacity to consent to their confinement, both the objective and subjective elements of the test for a deprivation of liberty will be met.
A number of criticisms have been raised in response to the court’s decision in Cheshire West, and how this has been applied in practice.
Some of these are set out in various submissions before the UK Supreme Court. See, for example, paragraphs 52 to 55 of the Secretary of State’s written case. They include:
- That it is too resource heavy. There are currently a staggering number of Deprivation of Liberty Orders (DoLS), resulting in significant assessment wait periods. This is exacerbated by the fact that where a person moves to a new placement, a new authorization is needed;
- That, as a result, people are being unlawfully deprived of their liberty for a very long time, and there is an attendant risk that a number of people will risk being detained inappropriately and/or in circumstances where they have capacity to make decisions about where to live and receive care.
- That the interpretation of what Article 5 requires in Cheshire West goes too far (Mr Justice Mostyn has led this charge.)
Elsewhere, in European Court of Human Rights and Mental Health (Eldergill, Evans and Sibley (2024), Bloomsbury Professional, London), Anselm Eldergill set out 17 relevant issues that need to be understood or considered when deciding if someone in a care setting is deprived of liberty.
Eldergill believes the Cheshire West approach does not properly distinguish between capacity, liberty, and autonomy. In his view, one of the relevant factors is what he calls the ‘but for’ test (‘Eldergill test’), where the decision maker must ask, ‘What are the things this person can do and wishes to do (‘wills’) but has not done because we have interfered or are interfering with their freedom to do them?’
Where a person has advanced dementia or a significant brain injury, Eldergill argues that the answer may be nothing or not enough to constitute a deprivation of liberty. The individual’s ability to act autonomously, to be self-directing, has been reduced not by restraints on their freedom imposed by others but by their own reduced abilities. The effect of their increasing dementia ‘is that they are now incapable of doing many of the things which previously they were able to do. Although they may be wholly unable to self-care, and so be under our complete care and supervision, we are not interfering with, limiting, or ‘controlling’ their liberty to do anything which they can do. Hopefully, we supervise and control what others do to them or for them but at this stage their own actions are not being controlled by others.’
However, others – including Mencap, Mind and the National Autistic Society, who intervened in the AG’s Reference – are concerned that if ‘deprivation of liberty’ is defined more narrowly, than in Cheshire West, there will be a loss of important procedural protections for people who are vulnerable by reason of disability. In Cheshire West, Lady Hale decided, for similar reasons, that there is a need to err on the side of caution when deciding what constitutes a deprivation of liberty. [§57]
Article 5 in the National Law Context
Deprivation of liberty’ is a phrase that appears in international standards, each time with a different context and emphasis and several international institutions are also concerned with the right to liberty and security of person.
They include most obviously the definition given in Article 5 of the European Convention on Human Rights, which is enforceable in the UK by reason of the Human Rights Act 1998 (HRA 1998). It is also incorporated by section 64(5) Mental Capacity Act 2005 (‘MCA 2005’) which provides that ‘deprivation of liberty’ has the same meaning in domestic law as it has in Article 5 ECHR.
The safeguards against arbitrariness required by Article 5 in the UK mental health Context are also contained in the MCA 2005. This gives authority to deprive a person of their liberty in only three circumstances: first, where the Court of Protection authorises it; second, where it is authorised under the Deprivation of Liberty Safeguards scheme set out in Schedule A1 of the MCA 2005); and third, in certain emergency cases on an interim basis, where an application has been lodged at court, and pending court approval.
These UK law provisions attempt to ensure that deprivations of liberty of people with mental health problems are subject to independent scrutiny in compliance with Article 5(4). They function as an important ‘gateway’ to such scrutiny. This is why it is important to have clarity as to the test for determining when a deprivation of liberty has occurred.
Article 5 in the International Context
International perspectives can provide insights that may be valuable when formulating the meaning of ‘deprivation of liberty’.
In terms of what amounts to a deprivation of liberty, the ECtHR has indicated that the objective limb of the test in respect of the concept of deprivation of liberty, which was the primary focus of Cheshire West case, is met in respect of “confinement in a particular restricted space for a not negligible length of time (the Storck test, which comes from case of Storck v Germany). This requires consideration of the concrete situation of the person concerned (differentiating between deprivation and merely restricting liberty).
The ECtHR has stated that “the key factor” in determining whether there was a deprivation of liberty in mental health cases is whether the management of the care homes in question exercised complete and effective control over the person’s treatment, care, residence, and movement. (see DD v Lithuania)
There is, however, a relative lack of Strasbourg case law on the factual situation with which the Supreme Court in Cheshire West was concerned, and about the ability of people who lack de facto capacity to make decisions about their care arrangements (i.e. who lack the ability to make such decisions as a matter of fact) to give valid consent.
This may, in part, be because of barriers to people who lack capacity in relevant regards bringing cases before the ECtHR (and domestic courts). Some member states have legal frameworks that prevent those who lack capacity as a matter of law (de jure capacity) from exercising some or all legal rights (see, e.g., ET v Moldova [2024] ECHR 858.) There are also strict time limits for bringing cases before the ECtHR, and which are more difficult for those who lack capacity to meet. The ECtHR’s mandatory representation rules (which require legal representation once a case has been communicated), combined with a lack of any settled policy for providing representation to persons lacking capacity has led, on occasion, to cases being struck out where they may otherwise have proceeded. Finally, litigation concerning the rights under the Convention for those who lack de jure or de facto mental capacity to make certain decisions is still a relatively recent phenomenon.
As well as the ECHR, there are also various other international instruments and bodies which are important in relation to the understanding of contemporary attitudes towards the right to liberty in a mental health context. These include the European Committee for the Prevention of Torture and Inhuman or Degrading Treatment or Punishment (“CPT”), the UN Convention on the Rights of Persons with Disabilities (CRPD), and bodies such theCommittee on the Rights of Persons with Disabilities (the CRPD’s supervisory body, which requires all states to report it every four years on progress towards implementation of the CRPD). The Convention on Human Rights and Biomedicine (the Oviedo Convention) and the Council of Europe’s Resolution 1859 (2012) on protecting human rights and human dignity are also of relevance to the meaning of “valid consent.”
Options open to the Supreme Court and the AIRE Centre’s application to intervene
It is not known whether the Supreme Court will maintain the status quo, moderate the Cheshire West test or reverse it totally. Its decision will have important consequences for large numbers of people who are confined to care homes, hospitals, and other settings, and who may lack capacity to challenge this confinement.
As Peter Mant KC and Nicola Kohn observed in their post on the Attorney General’s reference, it is inevitable that in many cases, the Supreme Court Justices will not have intimate subject-matter knowledge. This is where intervenors, as well as specialist lawyers, can be of value. The AIRE Centre had hoped to assist the court in making this decision by drawing on its expertise in European human rights law, and its international context. We hoped, in particular, to assist by:
- Surveying the case law on the importance, and function of Article 5 within the context of the Convention, including:
- Its essential purpose of protecting against arbitrary deprivations of liberty;
- Its importance within the convention – it, along with Articles 2, 3 and 4, is within the “first rank” of Convention rights), which is of potential relevance to arguments concerning the interplay between Article 5 and 8 rights;
- The state’s positive obligations under Article 5, which include taking steps to protect against arbitrary deprivations of liberty of which they know or ought to have known;
- Particular obligations towards people who lack (or may lack) capacity to challenge an objective confinement themselves, and the procedural protections that are required as a result. These include, for example, an obligation to ensure that their right of challenge does not depend on the exercise of discretion by a third party, to ensure that they are afforded independent representation, and to make sure that they are not only entitled but enabled to challenge a deprivation of liberty.
- Surveying the case law on the subjective limb of Article 5, and examining how this may apply in the domestic law context;
- Drawing on relevant principles from the broader, international law context, including:
- The approach to valid consent in the Oviedo Convention and Resolution 1859 (2012) on protecting human rights and human dignity; and
- Case law that sheds light on the approach to valid consent across Contracting States;
The AIRE Centre was represented in its application to intervene by Peter Mant KC, and Nicola Kohn of 39 Essex Chambers, instructed by Sarah Westoby of Leigh Day, all acting pro bono.
Matthew Evans is Director of the AIRE Centre. Prior to this he was Director of the Prisoners Advice Service and in private practice, where he specialised in mental health, community care and public law. He has been involved in 20 cases before the UK Supreme Court and numerous cases before the ECHR. He is a co-author of European Court of Human Rights and Mental Health published by Bloomsbury in 2024
Eleanor Sibley is a barrister at Garden Court Chambers and the AIRE Centre. Her areas of practice include Court of Protection and related areas of human rights law. She was junior counsel in Re D (A Child) [2019] UKSC 42, which concerned the meaning of ‘deprivation of liberty’ for 16- and 17-year-olds who lack capacity to consent. She is a co-author of European Court of Human Rights and Mental Health.
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