Police in London are making increasing use of journey information logged by people using Oyster cards. The smartcards store information on all bus, train and tube journeys taken in the last two months.
In 2004, the Metropolitan Police made just seven requests for travel information. But in January of this year alone the Met asked for travel information on 61 people. This increase is partly explained by the increasing use of Oyster cards.
The police have almost always been granted their requests - in 229 cases out of the total 243 they were granted the information requested.
A spokesman for Transport for London told the BBC that it does not pass information onto companies and only responds to written requests from the police. More from the Beeb here.
The cards are provided by TranSys - a consortium made up of EDS, Cubic Corporation, ICL and WS Atkins. ®