London, July 4 : Satellite navigation systems like in-car and portable GPS receivers are proving to be a boon for crime-fighters, say London's Metropolitan Police.
Forensic experts have revealed that the Met's detectives have used records of people's past movements stored by such satnav systems to investigate kidnappings, child grooming, murder, and terrorism in recent months.
They say that gadgets based on the satnav technology can store hundreds of records of recent locations visited, which may be helpful in finding a person's home.
According to them, the records also include 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, and found that they often retain records of past locations.
She said that old records had their file names removed, but were 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," New Scientist magazine quoted Nutter as saying.
Nutter attributes the police's knowledge about this technology to the editable web pages that satnav enthusiasts run to share information on the devices.
She said that such web pages provided more information on the workings of the devices than the manufacturers did.
The researcher also said that many a times suspects inadvertently gave the police further unwitting assistance by pairing their cellular phones to a GPS unit via a Bluetooth wireless link, which would load into the device personal data like incoming and outgoing calls, contact lists, and text messages.
Howeve, a data privacy expert at the Oxford Internet Institute, Ian Brown, said that growing awareness of data privacy could have an impact on such investigation procedures.
"It seems likely that secure deletion of personal data will become a popular feature of this type of device sooner rather than later," he said.
A report on the use of satnav systems by cops appears in the journal Digital Investigation.