GPS technology

I’m aware of one case in the military where the NCIS used GPS tracking (after getting a warrant). Fourthamendment.com recommends:

The D.C. Circuit held on Friday that a warrant is needed for prolonged GPS surveillance, recognizing People v. Weaver from New York and limitingKnotts. [This is a highly important decision. Every criminal and constitutional lawyer needs to read it.] United States v. Maynard, No. 08-3030 (D.C.Cir. August 6, 2010)[.] Two circuits, relying upon Knotts, have held the use of a GPS tracking device to monitor an individual’s movements in his vehicle over a prolonged period is not a search, United States v. Pineda-Moreno, 591 F.3d 1212 (9th Cir. 2010); United States v. Garcia, 474 F.3d 994 (7th Cir. 2007), but in neither case did the appellant argue that Knotts by its terms does not control whether prolonged surveillance is a search, as Jones argues here. Indeed, in Garcia the appellant explicitly conceded the point. … In a third related case the Eighth Circuit held the use of a GPS device to track a truck used by a drug trafficking operation was not a search. United States v. Marquez, 605 F.3d 604 (2010). … In each of these three cases the court expressly reserved the issue it seems to have thought the Supreme Court had reserved in Knotts, to wit, whether wholesale, or mass electronic surveillance of many individuals requires a warrant. Marquez, 605 F.3d at 610; Pineda-Moreno, 591 F.3d at 1216 n.2; Garcia, 474 F.3d at 996. As we have explained, in Knotts the Court actually reserved the issue of prolonged surveillance. That issue is squarely presented in this case. Here the police used the GPS device not to track Jones’s movements from one place to another, Knotts, 460 U.S. at 281, but rather to track Jones’s movements 24 hours a day for 28 days as he moved among scores of places, thereby discovering the totality and pattern of his movements from place to place to place.