Criminal cases are being abandoned because digital evidence is not available to bring or continue prosecutions, the forensic science regulator has said.

A report by Gillian Tully, the government-appointed regulator, states that police forensic science units no longer have the resources to deliver services to the required standards.

The problem has been “exacerbated” in the area of digital forensic science, which includes data from mobile phones or computers. The report, published today, says: “There are reports of cases being discontinued because the digital evidence is not available.”

Dr Tully wrote that critical shortfalls in the ability of police to extract information from hard drives was also causing trials to collapse. Sources in her office said that the information on cases being discontinued was based on discussions among professionals in the forensic science sector and anecdotal evidence they had shared with her.

Police leaders and the Crown Prosecution Service have highlighted the huge growth in the volume of digital material gathered as part of crime investigations, particularly now that most people use smartphones. The average handset contains vast amounts of data including messages, photographs and video, as well as internet browsing records and communications on social media and apps. Police have said that in total the information on a device can equate to about 30,000 pages of paper records.

Officers are struggling to sift through the vast amount of potential evidence on devices such as smartphones

Officers are struggling to sift through the vast amount of potential evidence on devices such as smartphonesYUI MOK/PA

The issue came under scrutiny last year when several rape cases collapsed after critical information emerged only at the last minute. A review into the failings by the attorney-general’s office noted that the increase in digital material had presented prosecutors with an “unprecedented challenge”, and suggested greater use of technology such as artificial intelligence.

HM Inspectorate of Constabulary has previously said that forces were at risk of being overwhelmed by the volume of digital evidence being collected.