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A tale of two Acts: the Mental Health Act, the Mental Capacity Act, and their interface


In January the Department of Health and Social Care published its response to the Independent Review of the Mental Health Act and a consultation on its proposed changes. As you might expect with legislation that has been around since 1983 – the reforms extend to many areas of care.

For the most part the Mental Health Act (MHA) applies to people that need assessment and treatment for mental disorders but who cannot or do not consent to admission to hospital and treatment for those purposes. Use of the MHA allows people to be compulsorily detained and treated. However, for some people who don’t have the mental capacity to make that decision and are not objecting to admission or treatment – either the Mental Health Act or the Deprivation of Liberty Safeguards (DoLS) (part of the Mental Capacity Act) may apply, and the professionals involved decide which is most appropriate.

Think it sounds technical? You’d be right – but the Independent Review considered this area of legislation as potentially contributing to higher rates of detention, so understanding ‘how’ that decision is made is important in deciding whether legislative changes can address that.

Commissioned by the Department of Health and Social Care, The King’s Fund has been conducting research on exactly that question. Using a survey and qualitative interviews, the research captured data from more than 600 health professionals, including approved mental health professionals, section 12 doctors, approved clinicians, and best interests assessors among others.

Among our respondents, most reported encountering people to whom this decision applies at least once a month, if not weekly. And while this was most commonly people with dementia, it also applied to a wide range of mental disorders. So, while this issue may appear niche, it’s far from it.

The decision that professionals are asked to make is influenced by a range of factors, but notable is how capacity, objection and treatment are understood. This is perhaps best illustrated by my own experiences in conducting the research – for as much as one interviewee outlined their clear view on how these concepts should be interpreted, the following interviewee frequently described a completely different interpretation – with equal confidence and at times using similar practical examples. This isn’t to say that either was right or wrong but indicative of a lack of common understanding of the fundamental concepts that define who this decision applies to.

Our participants also reported examples of blanket rules that were applied to local decision-making within professional groups and different settings that restrict use of Acts. We can’t say the extent to which this happens or where – but it does mean that the rights afforded to people admitted and treated in some settings and areas of England may not be afforded to those in others.

This lack of clarity and consistency is of equal concern to those subject to detention. Presenting our findings to the Lived Experience Working Group of the Mental Health Research Policy Unit, members shared their own experiences of how concepts such as capacity had been inconsistently applied, an issue that can have devastating consequences. These insights also exemplify the importance of understanding the experience of people subject to these decisions and their carers – without which decisions are only guided by clinical views on what is least restrictive.

The most worrying findings from our research were the ways in which people are being unlawfully deprived of their liberty. Examples include the continued use of informal admission to mental health units for people who lack capacity to consent to admission and are not objecting, patients left ‘in legal limbo’ on wards having been deemed ineligible for either Act, and patients who are detained under the wrong legislation or no legislation.

With the long-awaited introduction of Liberty Protection Safeguards, an amendment to the Mental Capacity Act which will replace the DoLS, the government has opted to hold fast on further changes to Mental Health Act in respect of this decision – allowing for any impact of these changes on detention rates to be assessed. Yet our findings indicate that achieving systemic change is likely to require attention to the established cultures of practice that have grown up around the use of both Acts. In addition, efforts are required to address inadequacies in the provision and monitoring of the safeguards associated with both Acts to prevent people from being unlawfully detained. Without these government promises to afford people with dignity and rights when detained are likely to go unfulfilled.