Surrey Police has been rated ‘good’ in terms of its efficiency by a force watchdog, despite being told by inspectors its deteriorating 101 call response time was “not acceptable”.

A report released on Wednesday by Her Majesty’s Inspectorate of Constabulary (HMIC) - which independently assesses police forces – said the force was doing well in planning and using its resources to manage current demand.

Although it praised the fact the force had made savings of £8.2m last year, it said Surrey Police needs to improve its understanding of the current and likely future demand on police time.

Inspectors criticised officers for “missing opportunities to identify under-reported crime” as it slammed the force for its deteriorating 101 call response time over the last two years, with more than 25 per cent of calls in April going unanswered compared to 14.7 per cent the previous year.

It said: “This is not acceptable because members of the public are not getting a proper service from the police and the force cannot be confident that it has an adequate understanding of its real demand.”

Figures also showed that calls answered in less than 60 seconds in April had slumped to 40 per cent, down from 57 per cent last year, although inspectors added the force plans to tackle this problem.

Inspectors also acknowledged Surrey Police had adopted a new model to obtain more information from callers to “identify the appropriate response”, but it meant more calls  going unanswered and “victims may be deterred from reporting crimes”.

In response, the force said it is piloting a scheme in one division where officers can make entries into the crime reporting system themselves without relying on the control room staff, and is expected to save 960 hours of operator time.

A “more sensitive caller queue management system” for 101 calls will also be introduced.

Inspectors also queried whether the force had a complete understanding of “so-called hidden demand”, such as tackling child exploitation, emerging crimes such as cyber- crime, hate crime and modern slavery, saying the force was developing this but there were some gaps.

For example, the force’s strategic risk assessment for the next financial year “identifies actions that it is planning in response to a variety of emerging crimes” but makes “no reference to how it intends to tackle some other types of hidden crime, such as female genital mutilation or forced marriages”.

Inspectors said: “Surrey Police should develop its understanding of current and likely future demand, especially in respect of 101 calls, ensuring that it has analysed appropriate information and intelligence from wider sources.”

Surrey Police was given good ratings in other areas of the report, which praised the force’s financial efficiency in planning to reduce spending by £7m in the next three years through a partnership with Sussex Police.

This would see both constabularies using estates, dogs, vetting, joint back office services, contact and deployment and upgrading of IT services and digitalisation.

Inspectors also praised the force for increasing staff in its custody suites, meaning a 45 per cent reduction in the time to be booked into custody was down to 14 minutes.

Fewer people in Surrey were being brought into custody “unnecessarily”, and dealt with in other ways, with more than 2,300 detainees fewer than in the previous year booked.

This included a 26 per cent reduction in the number of children brought into stations.

People with mental health issues were also being cared for by the NHS instead of being held in cells.

David Munro, police and crime commissioner for Surrey, said: “The Force has made great strides in understanding and meeting the demands of modern policing.

“This has been achieved at a time when police budgets remain tight so it is particularly pleasing that the reports notes the Force has sound financial plans in place for the future.

“Although great progress has been made in addressing those areas highlighted in last year’s inspection, we all recognise there is more to do to make Surrey a safer place for the people that live and work here.

“I am committed to working with the Chief Constable to ensure we meet these areas for improvement and sustain the efficient way Surrey Police works in the future.”