Bobbies on the beat are investigating burglaries, thefts and assaults amid a national shortage in trained detectives, the police watchdog has revealed.

High-volume crimes are being resolved over the phone or allocated to officers without the necessary experience or qualifications, according to a report from HM Inspectorate of Constabulary and Fire & Rescue Services (HMICFRS).

A quarter of victims in a sample of cases did not receive the service they should expect, the assessment found.

Failings included opportunities to gather evidence not being followed up or potential lines of inquiry being missed.

Many of the forces we inspected are in general providing a good service to the public but all are faced with competing priorities that if not managed correctly could see this service deteriorate Matt Parr, HM Inspector of Constabulary

HM Inspector of Constabulary Matt Parr said: “It used to be that you would have your CID, your response force, your community policing and they all had very discrete jobs.

“Response officers didn’t do investigations. Now they do. They don’t have the same accreditation, they don’t have the same experience.”

HMICFRS said investigations had become more complex because of the growth of online crime, the need to examine data on personal devices and improvements in identifying vulnerable victims.

While high-risk probes were allocated to specialist investigators, frequently committed offences, such as burglary and theft from vehicles, were often resolved over the telephone or assigned to neighbourhood or response officers.

75% The percentage of theft offences that had 'effective' investigations

“These officers often don’t have enough formal training and qualifications in investigation,” the report said.

Inspectors reviewed 2,608 randomly selected files from crimes recorded in the first three months of last year.

They found that 75% of theft offences and 76% of common assaults had “effective” investigations.

The report said: “This means a quarter of these complainants aren’t getting the service they should expect.”

The trend has emerged amid a shortfall in detectives and investigators, which the inspectorate has previously described as a “national crisis”.

HMICFRS said there had been some progress, with the deficit falling from 19% to 14%, but warned it would be a “few years” before all vacancies were filled.

Mr Parr said: “There’s a shortage of detectives to do the routine detective work, and very often it’s being farmed out to people who do their best but are not trained at the same level.”

We recognise new demands are putting pressure on the police and we are committed to ensuring they have the resource they need Home Office

The report – an overview of general findings that emerged in inspections of 14 forces – also found:

– Local policing is being “eroded” as neighbourhood officers are re-deployed, limiting their engagement with communities;

– Pressures of increased demand are stretching forces’ ability to root out corruption and having an adverse effect on officer well-being;

– The number of 999 calls increased by 5% nationally to nearly 10 million in 2017/18;

– At the same time there was a 3% fall in calls to the 101 non-emergency number, prompting the inspectorate to suggest the public are “losing confidence” in the service.

The inspectorate concluded that police were delivering a good level of service with “dwindling resources”, but warned that “cracks in the system” were widening.

Mr Parr said: “Many of the forces we inspected are in general providing a good service to the public, but all are faced with competing priorities that if not managed correctly could see this service deteriorate.”

Police resources have repeatedly come under the spotlight following funding reductions and a fall of nearly 20,000 in the number of officers from 2010 to 2018.

Last year a Commons report warned policing risked becoming “irrelevant” amid vanishing neighbourhood presences and low detection rates.

A Home Office spokesman said: “We recognise new demands are putting pressure on the police and we are committed to ensuring they have the resource they need.

“This is why we have provided more than a £1 billion increase in police funding compared to last year, including Council Tax and funding to tackle serious violence.

“We are pleased to see detective capacity has increased by 5% this year, but are clear that forces must continue to make progress on reducing the shortfall to improve their investigative capabilities.”

National Police Chiefs’ Council (NPCC) chairman Martin Hewitt said the inspectorate had graded the majority of forces as either good or outstanding.

He added: “Police chiefs, along with many others working in policing, have been very clear that the service is under severe pressure and requires additional long-term funding.”

The NPCC said it was working with other policing organisations to address challenges in recruiting and retaining detectives.

– The 14 forces inspected by HMICFRS were: City of London, Cumbria, Durham, Dyfed Powys, Essex, Gloucestershire, Greater Manchester, Humberside, Kent, Leicestershire, Norfolk, Nottinghamshire, West Midlands and Wiltshire.