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Why satnavs are a detective's best friend

Why satnavs are a detective's best friend

作者:米五萄  时间:2019-03-02 10:17:00  人气:

By Paul Marks (Image: Andrew*) The way in-car and portable GPS receivers store records of their owner’s past movements is a boon for crimefighters, according to London’s Metropolitan Police. In recent months the Met’s detectives have used data recovered from satnav systems of suspects to investigate kidnappings, child grooming, murder and terrorism, forensic experts say. The gadgets can store hundreds of records of recent locations visited, revealing, for example, a person’s home. It also includes information on the destinations a potential criminal may have typed into a unit. Beverly Nutter, forensic analyst at the Met’s Computer Systems Laboratory studied gadgets made by market-leader TomTom of the Netherlands. She found that they often retain records of past locations – old records have their file names removed but are not properly erased. “The persistence of the records for the TomTom, I think, is more to do with the way data is moved around when new records are added to the [mapping] file. The edited file is written to a new location and the older version remains until overwritten,” Nutter told New Scientist. Satnav enthusiasts who run wikis – editable web pages – to share information on the devices have unknowingly helped the police discover this. They provide more information on the workings of the devices than the manufacturers do, says Nutter. For example, the Opentom wiki helped the investigators understand TomTom data. Some suspects have inadvertently given the police further unwitting assistance, by pairing their cellphone to a GPS unit via a Bluetooth wireless link. That loads a treasure trove of personal data into the device, including incoming and outgoing calls, contact lists and text messages. But data privacy expert Ian Brown of the Oxford Internet Institute, UK, says growing awareness of data privacy could change all that. “It seems likely that secure deletion of personal data will become a popular feature of this type of device sooner rather than later,” he says. A 1995 European Union directive states that companies using personal data should collect what they need to provide a service and no more. This could lay the gadget-makers open to legal challenges, he adds. A spokesman for TomTom in Amsterdam insists it strives to guard its users location data against everyday intrusions, pointing out that a PIN code is needed to use a device. Police analysts sidestepped this process by making a copy of the data on a device’s hard drive or flash memory. TomTom was unaware that the Met was reporting on the forensic use of its products, but has worked with forces before. “However, we only turn device data over to the police if we receive a court order,” the spokesman points out. Brown recently co-drafted a UK government whitepaper urging companies to design privacy-preserving features into systems from the start. “It’s a lot harder to do anonymisation than people think,” he says. Journal reference: Digital investigation (DOI: