&gt;They&#x27;re giving over the information to a third party, which usually destroys any 4th amendment rights.<p>Same reason that there is no need for a warrant to collect phone calls since you are handing data over to the phone companies to carry between you and the other party(ies).  Also the same reason the government can shift through your mail, since the items are in the possession of a third party (you likely gave the items to the government itself).<p>To me this makes as much sense as the argument that since a plane carrying people can fly over you, it is perfectly reasonable to put a blimp with an extremely high zoom camera on that spies on your home constantly, detecting not just visible light, but also infrared.  Also, since when you talk things vibrate, and since it is possible to view those vibrations though a window, I&#x27;m actually broadcasting my speech to the public and thus don&#x27;t have any expectation of privacy.