Police struggle to cope with backlog of digital evidence

A Freedom of Information Act request from the PA news agency has found that 12,122 devices including computers, tablets and phones, are still awaiting examination across 32 forces.

The backlog figure has remained the same size for the last year which suggests there are not the resources to properly analyse the wealth of evidence, potentially hampering prosecutors in criminal cases.

A Times investigation undertaken last year showed very similar numbers, with 12,667 devices awaiting examination from 33 police forces.

Simon Kempton, the technology lead for the Police Federation of England and Wales, said investigators are “overwhelmed” by the amount of digital evidence they must deal with.

“The fact the number of digital devices waiting to be analysed has not budged from last year shows how overwhelmed investigators are with the sheer volume of digital evidence,” he said.

“Forces are struggling to attract new detectives which is resulting in mounting workloads.

“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.”

With lockdown procedures putting restrictions on the movement of people, online crime has ramped up in recent weeks with hackers using panic over the pandemic to steal people’s data while valuable supplies like face masks and test kits are being sold on the dark web.

Coupled with the impact that the virus will have on the number of working police, the evidence backlog could be exacerbated further in the coming months.

Kempton said the backlog can lead to problems with disclosure, where key evidence is not passed to defence teams during criminal trials.

“Having the extracted data is one thing, but analysing possibly hundreds of pieces of potential evidence from just one device once you’ve obtained it is quite another, taking a huge amount of time and skill – so we not only need to bring the number of detectives back up, but we also need to enhance their digital forensics skills.

“The biggest issue with having a backlog of devices is it resulting in disclosure issues, with potentially vital pieces of evidence not making it to court in time.”

London's Metropolitan Police estimated that 60 per cent of its exhibits would take three months to examine; 39 per cent would take three to 12 months; and 1 per cent would take more than 12 months.

The Forensic Capability Network (FCN) was launched earlier this month to create a more unified approach between police forces and boost standards in forensics.

National Police Chiefs’ Council lead for digital forensics Deputy Chief Constable Nick Baker said: “The majority of police investigations necessitate some investigation of digital devices, and the process of identifying reasonable lines of inquiry, extracting the relevant material from devices and reviewing it is time-consuming, so there will always be a pool of digital devices to be investigated.

“But 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.”