The Supreme Court ruled unanimously Monday the authorities need a probable-cause warrant from a judge to affix a GPS device to a vehicle and monitor its every move. http://www.wired.com/threatlevel/2012/01/scotus-gps-ruling/
Scalia: “Whatever new methods of investigation may be devised, our task, at a minimum, is to decide whether the action in question would have constituted a ‘search’ within the original meaning of the Fourth Amendment. Where, as here, the government obtains information by physically intruding on a constitutionally protected area, such a search has undoubtedly occurred.”
One's automobile has special status concerning illegal search, etc. Police may order the driver and any passengers out of the vehicle. If they have reasonable suspicion to detain you, police may frisk the outside of your clothing to check for weapons, but only if they have a basis for suspecting you're armed. If police detain and frisk you, you have the right to clearly state your refusal to consent to the search. They can only search your vehicle if they suspect something, see something plainly in view, or you're being arrested anyway. BTW, I'm not a lawyer, I only play one on... the internet??
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