The Metropolitan Police Service (MPS) has leased new mobile equipment that can strip phone data in minutes and store the data indefinitely, regardless of whether or not the owner has committed a crime.

The device, the ACESO, can extract texts, emails, pictures and contact details on the street from phones which the Met believe may have been used in criminal activity. A Met Police spokesperson confirmed to the Huffington Post UK that the ASECO lease began at the beginning of May and they are already being used across London.

The hiring of the devices is an attempt by the Met to speed up criminal investigations. Standard procedure currently involves sending phones away for forensic analysis, taking weeks to analyse.

However, the Met Police said that the "data recovered from the devices is retained and handled in accordance with other data and information held by the MPS (Metropolitan Police Service)."

When asked by the Huffington Post UK how long data is kept, a Met Police spokesperson said that data is retained "for the forseeable future," with no timeline for deleting information.

This could mean that some members of the public will have their entire phone's contents stored for an undefined period of time even if the phone owner is never charged with an offence.

Radio Tactics, the company behind the ACESO, says that the Met has leased 16 of the devices, one for each London borough, for 12 months at a price of £50,000. This price includes the cost of training 320 officers to use the device.

Radio Tactics says that the device "empowers police officers with the ability to examine and interrogate digital mobile devices, quickly and accurately," making it particularly useful where "immediacy of information is paramount to the success of an operation."

The Met's Deputy Assistant Commissioner, Stephen Kavanagh, said: "Our ability to act on forensically-sound, time-critical information, from SMS to images contained on a device quickly gives us an advantage in combating crime, notably in terms of identifying people of interest quickly and progressing cases more efficiently."

However, civil liberties group Liberty has questioned the legality of the new technology. Director of Policy Isabella Sankey told the Huffington Post UK: "It is unclear whether the police have legal authority for such intrusive access. Just as retention of innocents’ DNA came unstuck in the Court of Human Rights so too could this dangerous policy of stockpiling intimate details about those never charged, let alone convicted."

"Emptying your pockets at the police station used to mean giving up your spare change and a bus pass. Now the police think they can demand copies of text messages, emails, photos and contacts to be kept by them forever. "

Another dissenting voice against the Met's new equipment is data protection lawyer Vinod Bange, of the firm Taylor Wessing.

According to Bange, it is crucial to know how long the Met plans to keep hold of data.

"Unless there are strong arguments as to why that information should be retained for evidential reasons, which is already questionable when a suspect is released, then it’s very difficult to see that there is a lawful basis for that mobile device data being retained by the police," he says.

The public have a right to know if a third party such as the police has their data, for what purpose and for how long it will be held. Photos of your family, automatic access into Facebook and Twitter, will all that data be extracted from the mobile device?

"Will a suspect who is released without charge be told that their mobile has been accessed and the data retained even if they are no longer under investigation?

"These are all questions which the public should have answers to.”