Police have used partial fingerprints drawn from a WhatsApp photo in securing 11 convictions related to drug trafficking in Wales, U.K. Representatives of the South Wales Police told the BBC that the approach was “groundbreaking,” and highlighted the potential to leverage evidence found on the phones of suspects.
The crucial photo showed a man’s hand holding an array of ecstasy tablets, and was found in a review of the contents of a phone seized in an arrest in the town of Brigend. The phone also contained messages indicating it had been used in drug deals. The photo only showed a portion of a finger, but that was apparently enough to confirm a link to an existing suspect. The discovery helped prove a large conspiracy to distribute drugs.
South Wales Police also announced that they were able to locate £20,000 (about $28,500) worth of bitcoin in a dealers’ accounts, another first for the department.
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WhatsApp is well-known for its end-to-end encryption features, and the Facebook-owned company has worked to reassure users that they are protected from the kind of data-sharing that has recently drawn regulatory attention to Facebook. But while encrypted messages and photos are hard or impossible to collect remotely, they’re much easier to access directly from phones already used to send or receive them.
In this case, the photo was located on a phone acquired in an August 2017 raid, in which cocaine and a large quantity of marijuana were also seized. The photo was reportedly used to offer drugs for sale on WhatsApp. Another Facebook-owned platform, Instagram, recently filtered several hashtags used to market illegal drugs there.
Dave Thomas, a spokesperson for the South Wales Police, told the BBC he believed it was the first time a photo had been used to provide fingerprint evidence in Wales. Thomas said the incident pointed to the potential for social media images and other records to be used to identify and prosecute crimes.
