Orin Kerr writes:
This is my second post on United States v. Jones, the case on GPS and the Fourth Amendment. In this post, I want to explore whether the act of installing the device should count a Fourth Amendment search or seizure. My bottom-line is that I find this a surprisingly difficult and open question: Justices wishing to apply the Fourth Amendment in a way that is consistent with Fourth Amendment text, history, principles, and precedents could plausibly go either way. One implication of this uncertainty is that if the Justices decide to regulate GPS under the Fourth Amendment, focusing on the installation of the device is a much better option than trying to jump into the thicket of issues discussed in my first post about use of the device once installed. At the same time, it’s worth noting two additional wrinkles. The first is the uncertain standard of reasonableness that would follow from a conclusion that installing the device is a search or seizure. The second is the important role of statutory regulation, which may deal with some of the concerns raised by those who want the Supreme Court to construe the Fourth Amendment to sharply limit GPS monitoring.
Read more on The Volokh Conspiracy.