by Jonathan G. Cedarbaum
A year ago, in Carpenter v. United States, 138 S. Ct. 2206, 2217 (2018), the Supreme Court held that police acquisition of a defendant's historical cell-site location information (CSLI) from his cell phone provider constituted a search for purposes of the Fourth Amendment. In doing so, the Court upended some established Fourth Amendment doctrines and raised more questions than it answered about the constitutional limits on government acquisitions of digital data. Over the past year, lower federal courts and state courts have begun to grapple with Carpenter's implications - not only for CSLI collection but also for other forms of location monitoring and digital surveillance. Despite attempts by criminal defendants to extend Carpenter to internet protocol data, internet transaction history, cell-tower dumps, pole cameras and similar surveillance cameras, and even financial records held by banks, courts have applied Carpenter almost exclusively in situations involving historical or real-time CSLI.