The prime minister has criticised current legislation without explaining what will take its place

“I’m going to scrap the old Mental Health Act,” Theresa May said on Question Time last week. Her aim? To “introduce a new law which confronts the unnecessary detention that takes place too often.”

The Mental Health Act allows doctors to detain, assess, and treat patients experiencing a mental health problem which poses a risk to themselves or others, such as suicidal intent, psychosis, or mania. In a recent investigation by VICE magazine, one psychiatrist estimated that sectioning saves the lives of three patients a night in Hackney alone.

It is unclear which of these patients Theresa May believes have been sectioned inappropriately. Although featuring an admirable aim, her policy announcements have lacked any detail on how the number of “unnecessary detentions” might be reduced, or any evidence that patients have been inappropriately detained at all.

In fact, when the health secretary Jeremy Hunt was interviewed about the issue last month, his sole example of the Act’s “injustice” related to the sectioning of children in police cells. “If you have a child that has severe mental health problems and you find that the child ends up in a police cell, that is a terrible thing,” he told the BBC. Yet as the mental health charity Mind notes, the practice of sectioning children in police cells was prohibited by the government’s own Policing and Crime Act, introduced in January 2017. Scrapping the foundation of thirty years of mental health law would do nothing to help a problem already solved by existing legislation.

This isn’t to deny that there are valid reasons for questioning the current law. The Act is almost unique in UK law in allowing citizens to be detained based on the risk they pose to others, without any crime having been committed. Concerns that legislation discriminated against mentally ill patients led to the recent introduction of a “fusion” law in Northern Ireland, which makes no distinction between mental and physical health conditions. Rather than focusing on the risks a patient poses, the Northern Irish legislation assesses a patient’s capacity to make decisions about their treatment.

However, it’s unclear whether Theresa May objects to the Mental Health Act for similar reasons. The Conservative manifesto offers only a fleeting mention of the act, but does state that it would be replaced by a “Mental Health Bill,” suggesting her proposals wouldn’t follow the integrative legislation introduced in Northern Ireland.

When the prime minister announced her plans to scrap the act, an accompanying press release featured a quote from the Care Quality Commission, the independent regulator of healthcare services. The quote pointed to “failings that may disempower patients, prevent people from exercising legal rights, and ultimately impede recovery.” What the quote missed was the words immediately preceding it in the CQC’s original report; “these are not technical issues of legal process.” As Musa Sami, a psychiatrist and researcher at King’s College London, noted in the British Journal of Psychiatry, “the CQC’s criticism is that standards applied by the act are not being upheld. This is quite different to suggesting the legislation is flawed in itself”.

In fact, when it was announced last year that the number of patients detained by the act was at record levels, nobody within the medical profession believed the legislation was to blame. Steve Chamberlain, the head of a national network of Approved Mental Health Professionals, attributed the statistics to funding pressures. “Resources for community services are more and more stretched, it’s often very difficult to find any other response than detaining someone to hospital” he summarised. Given that almost one in three patients sectioned in the past year have been admitted to private hospitals – a decision doctors take when there are no NHS beds available – it seems more likely that cuts to mental health services are responsible for the recent crisis than a thirty-year old piece of legislation.

Theresa May flippantly talks about “ripping up” the Mental Health Act, but doesn’t seem to understand the consequences of doing so. There were over 63,000 detentions made under the Act last year, and it provides structure to much of adult inpatient psychiatric care. On the ward where I currently work, more than nine out of ten patients–most either psychotic or suicidal–are admitted under provisions made by the Act.

Many of these patients have requested leave from the ward in order to vote this coming Thursday. If Theresa May is intent on “ripping up” the legislative basis of their care, she should respect the dignity of these patients, their families and their doctors by opening her proposals to expert scrutiny and public debate. Without knowing the details of her plans, how can any voter be expected to endorse them?

Instead, Conservative party policy is revealing what experts scrutinising the Mental Health Act have known for over thirty years. It is easy to criticise medical law, but far more difficult to propose a viable alternative.

George Gillett is a student doctor and freelance journalist. He tweets at @george_gillett

Competing interests: None declared.