I previously wrote about the pending case of United States v. Jones and the effort of the Administration to establish precedent allowing the government to follow citizens with Global Positioning Devices (GPS) without any showing of probable cause. I am happy to report that the rule has ruled unanimously against the government and found the practice to be unconstitutional under the fourth amendment. It is a stinging defeat for the Obama Administration but a roaring victory for privacy and civil liberties at a time when good news is rare.

In my prior column, I discussed the limits of the Katz test created in Katz v. United States, 389 U.S. 347. Much of the debate between the justices focuses on this test and its progeny.

The Court divided between a majority opinion penned by Associate Justice Antonin Scalia, concurrences by Associate Justice Sotomayor and Associate Justice Alito.

Scalia emphasizes that privacy protections are broader than the “reasonable expectation of privacy” test:

The Government contends that several of our post-Katz cases foreclose the conclusion that what occurred here constituted a search. . . . But as we have discussed, the Katz reasonable-expectation-of-privacy test has been added to, not substituted for, the common-law trespassory test. The holding in Knotts addressed only the former, since the latter was not at issue. .