December 20, 2017
On November 29, 2017, the Supreme Court heard oral argument in Carpenter v. United States, which presents the question of whether the federal government must, under the Fourth Amendment, obtain a warrant before getting historical cell-site location records from cell phone service providers. Broadly speaking, the government argued that it did not need to obtain a warrant because individuals do not have a reasonable expectation of privacy in business records held by third parties (in this case, the cell service providers). Carpenter countered that the warrantless collection of data revealing people’s long-term movements so violates reasonable expectations of privacy that a warrant is required, notwithstanding that the data is possessed by third parties. [...]