The Court today reached the right result for the wrong reason. The majority extends the “reasonable expectation of privacy” to cell-site location data and thereby carves an exception to the third-party doctrine—as well as making various caveats about not reaching different technologies, security-related investigations, and other hypothetical situations. Good enough for restricting law-enforcement overreach in some cases, but just adding cautionary barnacles to a rusty and outmoded Fourth Amendment hull.
It’s Justice Neil Gorsuch who’s right that we need to go to the theory of the matter and the people’s right to be secure in their “persons, houses, papers, and effects” based not on privacy expectations but on property rights, contract law, and statutory protections (all of which can certainly be applied in the modern digital age). This very much aligns with what Cato argued in our amicus brief. Gorsuch styles his opinion as a dissent because he adjudges that Carpenter’s lawyers didn’t “preserve” such arguments, but it’s a concurrence in all but name.
If the Court doesn’t follow that philosophical line, going back to first principles rather than reinventing the Fourth Amendment with each technological revolution, its jurisprudence in this area will never escape the artificial muddle epitomized by the unsatisfying majority opinion here.
[This may be updated and my colleagues are likely to have more analysis.]