Police officers are "confused" about the legalities of using tools to extract content and data from people's phones, and increasingly conducting what has been described as "digital stop and search".
That's the warning of Privacy International, which claims that there is a potentially "unlawful regime" emerging in Britain's police forces, in which officers may be abusing the use of mobile extraction tools.
It claims that police are using these systems without "clear safeguards for the public" and "no independent oversight", allowing the "abuse and misuse of sensitive personal".
After researching "ongoing issues of discrimination within the criminal justice system" and the use of mobile phones in the forces, the organisation said it has identified a "serious cause for concern".
Police are using highly intrusive technology to extract and store data from individual's phones, on a questionable legal basis
Privacy International submitted a range of Freedom of Information requests across the country and found that 26 out of 47 police forces (55 per cent) are currently using mobile phone extraction systems.
As for the other 21 police forces, eight of them (17 per cent) have trialled or are beginning to use this technology, and thirteen (28 per cent) ignored the questions or said they had no relevant information.
Forces are purchasing systems from companies such as Cellebrite, Radio Tactics and MSAB.
And 12 forces admitted that they have self-service kiosks for extracting data from people's electronic devices while investigating both low-level and serious crimes; thirteen, meanwhile, use hubs that serve a number of forces.
"Privacy International has uncovered that, in the UK, police are using highly intrusive technology to extract and store data from individual's phones, on a questionable legal basis," said Privacy International.
"The technology, which has been rolled out nationally following its use by the Metropolitan Police Service during the London Olympics in 2012, gives the police the ability to obtain data from our phones than we cannot access ourselves and which we do not know exists.
"Without public consultation or parliamentary scrutiny, the police want extraction of data to be standard procedure in all criminal investigations.
To ensure that mobile extraction tools are not abused by the forces, Privacy International said there "needs to be an urgent independent review into this widespread, intrusive but secretive practice".
Lawmakers, it argued, should implement "a requirement for police to obtain a warrant for searching the contents of a mobile phone, issued on the basis of reasonable suspicion.
The report also calls on the Home Office to "publish guidance for the public, regarding their rights if the police want to search their mobile phone".
"In the course of a search of your home, if the police confiscate your possessions, you are entitled to an inventory of those items," added the report.
"Yet if data is extracted from your devices, you may not even know this has taken place, let alone be told what kind of data the police have stored on their database."
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