There has been a 50 per cent reduction in the numbers of children arrested and taken into custody by West Midlands Police in the last two years.
According to the latest figures just 2,295 children was detained by officers during 2017/18, down from 5,412 during 2015/16.
It follows a policy shift under which custody is only used as a last resort for those under 18s either being investigated for the most serious crimes or where it is feared further offences may be committed.
But of those who are held, many are still sleeping in adult custody blocks due to a shortage of secure children's homes or foster carers in the West Midlands.
However during 2017/18 the police requested council places for 273 children, but just 29 were granted accommodation.
So police have to choose between sending children to a secure unit miles away from the region or kept in custody suites until a council place becomes available.
Last year Government inspectors warned West Midlands Police over the high numbers of children detained in custody over night.
“The local authorities have to step and do something. It is not acceptable for there to be no secure accommodation for children in the West Midlands.”
He said that police are talking to the councils to find secure places - and urging the seven boroughs to work on a shared facilities to cut costs.
Mr Jamieson also praised police: “There has also been a huge amount of work to reduce the number of children coming into custody. We have reduced that figure by 50 per cent. I agree with West Midlands Police that custody should be a last resort for children.”
A meeting of the commissioner’s strategic board was told that increasingly voluntary interviews and community resolutions for low level crime are being used to keep children out of custody.
Assistant chief constable Alex Murray said: “The arrest of a young person is considered carefully, acknowledging the emotional affect it can have and is a last resort. However, there are times when an arrest is necessary to prevent further offences, investigate a serious offence or for the protection of the young person or others.”
A similar approach, using voluntary interviews and changes to bail regulations, has also seen a drop in the over all custody rate - with almost ten thousand less a year being detained than three years ago.
In 2015/16 there were a total of 63,467 uses of custody, and last year this had fallen to 54,278. A 16 per cent fall.
In particular those identified with mental health problems are no longer being held and instead referred to health services for specialist help.
Mr Jamieson said: “Over 54,000 people went through went through West Midlands Police’s custody cells, this is lower than previous years due to law changes around bail conditions.”
“No one detained under the section 136 of the Mental Health Act was taken in to police custody. Instead they were taken to places of safety where they received specialist support, instead of ending up in a police cell.
“This is supported by the mental health triage service which responds to thousands of people each year. By ensuring that people suffering with mental ill health aren’t being taken in to custody we are saving money, but more importantly making sure that people get the treatment and support they require.”
In ten cases people who had been detained were later referred for mental health treatment after showing signs of issues in the custody suite.