You may think that law enforcement agencies could not plant a GPS tracker to a car without a warrant, but many people have woke up to the fact that until now, it was a growing practice, thanks to the falling prices of GPS devices. The Supreme Court has ruled that warrantless GPS tracking was unconstitutional and this extends to the position tracking of mobile devices as well (via the cell-tower locations triangulation, or direct GPS location). And although this is not explicit in the ruling, other forms of “electronic bugs” could (or should) be included as well. some also argue that the use of aerial drones should fall under the same legislation (what about manned helicopters then?).
It is not clear if this ruling will have consequences on current cases, but it would be natural that a certain number of defense attorneys plead that some evidence was gathered illegally. Interestingly, Declan McCullagh from CNET notes that California has taken the lead by introducing a law that requires a warrant to electronically track a person.
What do you think of this ruling, and where do you put the limit between the need for law enforcement information gathering and the privacy of the citizens?