Mental capacity after Cheshire West: what the 2026 Supreme Court ruling means for everyday care

For twelve years, care staff and managers in England relied on one question to decide whether someone was deprived of their liberty: the "acid test". Is the person under continuous supervision and control, and not free to leave? On 2 June 2026, the Supreme Court overruled the Cheshire West judgment that created that test. It is the biggest change to deprivation of liberty law in more than a decade, and it took effect immediately.

This article explains what has changed, what has not, and what it means on shift. It is general information, not legal advice. Your organisation's policies and local authority guidance should guide individual decisions.

What the Supreme Court decided

In [A Reference by the Attorney General for Northern Ireland [2026] UKSC 16](https://caselaw.nationalarchives.gov.uk/uksc/2026/16), the Court said the acid test was "wrong in principle". In its place is a multi-factorial assessment of the person's concrete situation, including:

• the type and degree of the restrictions
• how long they last and their effects on the person
• how the arrangements are put into practice
• whether the person objects or appears content
• the purpose of the restrictions and how normal the setting is

No single factor decides it. The Court also said a person can lack mental capacity under the Mental Capacity Act and still be able to give valid consent to their living arrangements for human rights purposes.

What has not changed

The Mental Capacity Act 2005 still applies in full, and its five principles matter as much as ever:

1. Assume a person has capacity unless it is established that they lack it.
2. Take all practicable steps to help a person make their own decision.
3. An unwise decision does not mean a person lacks capacity.
4. Anything done for a person who lacks capacity must be in their best interests.
5. Consider whether the purpose can be achieved in a way that is less restrictive of their rights and freedoms.

DoLS remains in force in care homes and hospitals where a person may be deprived of their liberty. The Liberty Protection Safeguards are still not in force. The government announced a consultation on them for 2026, and the timetable remains uncertain.

Why your records matter more than ever

Under the old test, the answer was often obvious from the care plan. Now the person's own wishes, feelings and behaviour are central, which puts frontline observation at the heart of the decision. Good practice from the guidance published since the ruling:

• Record wishes and feelings in detail. What does the person say about where they live? How do they behave when support is given?
• Record any objection or distress: when it happens, what triggers it and how the person settles.
• Don't treat silence as consent. A person who cannot express disagreement is not the same as a person who agrees.
• Note anything that restricts the person. Locked doors, sedating medication, restraint and limits on contact all matter.
• Escalate when the picture is mixed. If someone moves between seeming content and objecting, raise it with your manager so a DoLS referral can be considered.

What managers should do now

1. Review existing DoLS authorisations using a triaged approach, starting with the highest-risk cases. DHSC's interim guidance says leaving them in place while you review is not, by itself, unlawful.
2. Update your MCA and DoLS policy to remove reliance on the acid test.
3. Retrain your team. CQC's State of Care report for 2024/25 found staff who did not properly understand when DoLS applies, and the new test asks even more of them. Our article on evidencing training in practice covers how to show that learning has stuck.
4. Watch for new guidance from the Department of Health and Social Care and a revised Code of Practice.