A Fifth Circuit panel of Chief Judge Edith Jones, and Circuit Judges Patrick Higginbotham, and Leslie Southwick held that a borrower of a truck has "standing" to challenge the use of a slap-on tracker which sent out an intermittent signal accurate to 50 yards on that truck, but not to challenge the placement of the tracker on the truck. The Court's reasoning in this case, United States v. Jose Juan Hernandez, was that the truck was not his and that it was parked on a public street. He did not have a reasonable expectation of privacy that was violated by putting the tracker on the truck. Chief Judge Edith Jones's opinion contrasted the facts of this case with the facts United States v. Maynard, 615 F.3d 544 (D.C. Cir. 2010), cert. granted sub nom, United States v. Antoine Jones, No. 1259 (April 15, 2011) in which the GPS device continuously monitored a suspect for a month, which the D.C. Circuit found to be an illegal warrantless search. The Hernandez court appeared to think that Maynard is the only federal case which threw out a case on the ground that GPS tracking was an illegal search. The Hernandez device operated gave off pings on a regular basis. The government's agents found out how Hernandez had begun his drug delivery run, but after that, the battery in the device failed, and the agents tracked him the rest of the time by visual surveillance.
That the Supreme Court of the United States voted to hear Maynard/Jones makes me think it likely that the conservative wing of the court did not like the circuit opinion and wants to reverse it.
Hat tip to the weekly case summary of the Texas District and County Attorneys' Association.