...or Are You Just Happy to See Me?

This morning, you left the house tagged with a tracking device that the government can use to find out where you have been and where you are going.

I'm talking, of course, about your cell phone. Mobile phones communicate continuously with cellular towers in order to receive calls, sending out a signal registering its existence and identity with the provider's nearest towers. The provider stores this cell-site data, which can be triangulated to determine the customer's physical location.

While most courts considering the issue have held that police need "probable cause" to track your movements, a new decision (.pdf) last week out of the U.S. District Court of Massachusetts holds that law enforcement need show only "relevance to an ongoing investigation" to get a historical record of your past movement (something like the Jeffy trail in The Family Circus cartoon).

Why are courts treating past and prospective tracking so differently, and should they?

The problem starts with a basic congressional assumption that real-time information in transit is more private than stored information -- a bias that is enshrined in various laws that protect wire and electronic communications. Congress has imposed stronger limits on how real-time information is accessed and used.

 Source : Wired.com