"To the contrary, “what [one] seeks to preserve as private, even in an area accessible to the public, may be constitutionally protected.” Katz, 389 U. S., at 351–352. A majority of this Court has already recognized that individuals have a reasonable expectation of privacy in the whole of their physical movements. Jones, 565 U. S., at 430 (Alito, J., concurring in judgment);"
This is about the police planting a GPS tracker on someone's car - that's that "Jones" is referring to here. That case involved the police tracking someone in public and in private.