Under a US Department of Transportation pilot project initiated last year, special GPS tracking meters have been placed in the cars of volunteers around Seattle to keep tabs on where they go and how many miles they travel. The idea, part of a constellation of (generally progressive) proposals known as “value pricing,” is to track drivers using GPS technology and charge them to drive in certain places (like toll roads) and at certain times (like rush hour). The GPS trackers are placed inside vehicles, where they transmit information to a central government office, which bills drivers accordingly. (In Oregon, the information is beamed out to the DMV when a driver pulls into a gas station.)

According to an article on CNET, the US Federal Highway Administration is about to issue another $11 million round of grants for similar projects in other states.

The GPS transponders should, in theory, discourage people from driving at rush hour and encourage them to use public transit, because they charge drivers more when the roads are most congested.

But the GPS trackers differ from the similar EZ-Tag payment system used on toll roads nationwide in one important - and alarming - way: According to CNET, the program lacks any restrictions that would prevent state and law enforcement authorities from “continually monitoring, without a court order, the whereabouts of every vehicle on the road.”

According to the article:

No rule prohibits that massive database of GPS trails from being subpoenaed by curious divorce attorneys, or handed to insurance companies that might raise rates for someone who spent too much time at a neighborhood bar. No policy bans police from automatically sending out speeding tickets based on what the GPS data say.

The Fourth Amendment provides no protection. The U.S. Supreme Court said in two cases, U.S. v. Knotts and U.S. v. Karo, that Americans have no reasonable expectation of privacy when they’re driving on a public street.

Even more alarmingly, in Washington state, a federally funded report has suggested that the GPS bugs should be made “tamper-proof” by causing the engine to fail if the tracking device is disconnected.