A $37m electronic toll system in the San Francisco Bay area that can track a quarter of a million cars has raised fears that individual drivers will be monitored.
Developers say that the electronic toll system will provide motorists with real-time information about some of the nation's worst road congestion via mobile phone, radio or the internet, and give traffic planners crucial data on problem areas.
But the 'TravInfo' scheme has sparked concerns about how the data can be used, with fears that it could track individual car movements, according to the San Jose Mercury News.
Civil liberties groups have approached the Metropolitan Transportation Commission seeking guarantees that the system will not be used to find the location of individual drivers.
But TravInfo project manager Michael Berman said: "We're not tracking or trying to follow any individual car, just the overall traffic flow."
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