Essex Police has backlog of over 100 digital devices waiting to be searched for evidence

The Police Federation of England and Wales said officers are "overwhelmed" by the amount of digital evidence they are faced with, warning that mounting workloads are a result of forces struggling to attract new detectives.

Data provided to the Press Association news agency through a freedom of information request showed a total of 143 devices were awaiting examination by Essex investigators.

Essex Police has recently increased its mobile phone team to meet a growth in demand.

A spokesperson for the force said: "Many people rely heavily on digital devices and that includes criminals, so almost every criminal investigation involves extensively examining at least one device for evidence. These include computers, tablets, mobile phones and CCTV and sat nav systems.

"They are increasingly sophisticated and capable of storing and accessing increasing amounts of data, and therefore take longer to analyse.

"To manage this we prioritise cases where there is the highest harm and most risk to the public and vulnerable people, which accounts for around 20 per cent of cases.

"For all other cases, we aim to examine devices within 75 days. Some mobile phones have taken longer to examine because of rapidly changing technology, complex issues and the need to use advanced data recovery techniques."

Across England and Wales, a total of 12,122 devices were awaiting examination.

The figures, covering 32 police forces, were obtained by PA in February and March.

Although there is no local breakdown of what devices are being held, the most common items nationally include computers, tablets and phones.

These can be used to check messages, photographs, emails or social media accounts as part of an investigation.

Essex Police was one of five police forces in the East of England to provide figures – at least 1,660 devices are waiting to be examined by these forces.

Estimates for how long it would take to clear the backlog for the forces that could provide one ranged anywhere between three months to more than a year.

Simon Kempton, technology lead for the Police Federation of England and Wales, said: "Investigators are overwhelmed with the sheer volume of digital evidence.

"There is also a need for forces to invest in technology which can help speed up this process by extracting and sorting this data automatically."

A study by civil liberties group Big Brother Watch in 2017 found that 93 per cent of police forces in the UK extract data from digital devices seized as evidence from suspects, victims and witnesses.

The latest figures provided to PA show the devices are linked to a wide variety of crimes, including possessing indecent images of children, violent crimes, sexual offences, fraud and robbery.

Mr Kempton said the 43 forces in England and Wales have different approaches, with some using the latest technology to download and analyse data and others not.

A new Forensic Capability Network (FCN) was launched on April 1 to create a more unified approach between police forces.

National Police Chiefs' Council lead for digital forensics, Deputy Chief Constable Nick Baker, said it would help reduce the size of the backlog.

"The process of identifying reasonable lines of inquiry, extracting relevant material from devices and reviewing it is time-consuming,” he added.

"With the launch of the FCN and ongoing efforts to identify smarter working practices, we aim to see a reduction in the number of devices to be investigated at any one time."

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