The Met Police has made record requests for data on London commuters, a majority of whom use Oyster smartcards, the Green Party has said.
Transport for London (TfL) figures show the Met made 6,576 requests in 2010, but it was turned down 810 times.
Noel Lynch, chairman of London Green Party, called for “rigorous safeguards to protect people’s privacy”.
The Met said the rise in requests was due to the rise in Oyster usage as the data helps trace a person’s movement.
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