Police stations "should stop being used" as places to detain mentally ill people, according to the President of the Police Superintendents' Association of England and Wales.Ch Supt Irene Curtis says A&E would be a "better place" when mental health units are unable to take them.
Police can detain people where no crime has been committed but they suspect the person is mentally unwell. The temporary police power is called a section 136.
During 2011-12, 9,000 people were detained in police custody under section 136.
'National scandal' of crisis care
Care minister Norman Lamb has described the standard of some crisis care as a "national scandal."
Paul Jenkins, Chief Executive of Rethink Mental Illness, has also welcomed the highlighting of the issue, which he says requires "urgent attention".
“Far too many people with severe mental illness end up being detained by police because they can’t get the treatment they need. But a police cell is the last place that someone who’s hearing voices, feeling suicidal or self-harming should be," he said.
“Instead, we need to make sure that people who are in great mental distress are brought to a therapeutic setting where they can get the treatment they need. It would make a huge difference to the person involved, and would also be a much better use of police resources."
Must be better places than police stations
In highlighting the debate on the situation, Ch Supt Curtis said: "I think as long as there is an option to have a police station cell as a back-up then they will always be used and I think until you get to the stage where you actually say no, enough is enough, then police station cells should stop being used per se.
"If there are no spaces at the mental health unit, then my belief is that an accident or emergency unit at a local hospital must be a better place than a police station."
Freedom of Information requests by BBC Panorama to 52 mental health trusts in England suggest that the number of adult acute beds available in mental health units fell by 17% between 2008 and 2013.
This figure is based on data from 27 trusts and excludes trusts which have merged, taken on additional services or provided incomplete data.