Search and seizure – ‘Tower dumps’ – CSLI

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Where a defendant moved to suppress evidence obtained through search warrants for “tower dumps,” a Superior Court judge’s decision to deny the suppression motion should be affirmed in part and reversed in part, as the second of the two search warrants was sufficiently particular but the first warrant was not supported by probable cause.

“As law enforcement capabilities continue to develop in the wake of advancing technology, so too must our constitutional jurisprudence. To this end, we must grapple with the constitutional implications of ‘tower dumps,’ a relatively novel law enforcement tool that provides investigators with the cell site location information (CSLI) for all devices that connected to specific cell towers during a particular time frame.

“Here, the Commonwealth obtained search warrants for seven tower dumps, corresponding to the locations of six robberies and an attempted robbery that resulted in a homicide, all of which investigators believed to have been committed by the same individual. After analyzing the information contained in the tower dumps, investigators determined that the defendant had been near the scenes of two of the crimes. The defendant subsequently was charged with the robberies and the homicide, and he moved to suppress all evidence obtained from the tower dumps as the fruits of an unconstitutional search. A Superior Court judge denied the motion, and the defendant filed an application in the county court seeking leave to pursue an interlocutory appeal; the single justice reserved and reported the case to the full court.

“The defendant argues that the Commonwealth’s use of the tower dumps intruded upon his reasonable expectation of privacy, and therefore effectuated a search under the Federal and State Constitutions. He also contends that search warrants for tower dumps are per se unconstitutional because they necessarily lack particularity. In addition, the defendant asserts that, here, the warrants were not supported by probable cause.

“We agree that the government’s use of the seven tower dumps was an intrusion upon the defendant’s reasonable expectation of privacy, and therefore constituted a search under art. 14 of the Massachusetts Declaration of Rights. We do not agree, however, that warrants for tower dumps are per se unconstitutional. Accordingly, investigators may use tower dumps so long as they comply with the warrant requirements of art. 14.

“Here, the second of the two search warrants was sufficiently particular and supported by probable cause, and therefore the use of the information obtained from it does not offend the Massachusetts Declaration of Rights. The first warrant, however, was not supported by probable cause, and accordingly, any evidence obtained as a result of it must be suppressed. …

“While the decision we reach today is grounded in individual rights protected by art. 14, we recognize the potential invasions of privacy that could befall those innocent and uninvolved third parties whose CSLI is revealed once an application for a search warrant is allowed. … Unlike defendants in criminal cases, these individuals may never know that their CSLI was provided to law enforcement, let alone be able to exercise any sort of control or oversight over how their data is used. … Such a situation presents far too great a risk of unwarranted invasions of privacy, whether intentional or inadvertent, malicious or innocent. …

“Accordingly, in all future cases, only a judge may issue a search warrant for tower dumps. …

“The warrant must include protocols for the prompt and permanent disposal of any and all data that does not fit within the object of the search following the conclusion of the prosecution. …

“The Commonwealth’s actions in this case intruded upon the defendant’s reasonable expectation of privacy and therefore effectuated a search under art. 14. Nonetheless, because the second warrant was sufficiently particular and supported by probable cause, the evidence obtained pursuant to the second warrant need not be suppressed. All evidence stemming from the tower dumps provided pursuant to the first warrant, however, must be suppressed because the warrant was not supported by probable cause. Our decision is prospective, and also applies to those cases that are active or pending on direct review on the date of issuance of the rescript in this case. Henceforth, before acquiring and analyzing a series of tower dumps, the Commonwealth must obtain a warrant from a judge. Before issuing the requested warrant, the judge must ensure that it provides a protocol for the disposal of any data that falls outside the scope of the search.”

Commonwealth v. Perry (Lawyers Weekly No. 10-039-22) (52 pages) (Gaziano, J.) A pretrial motion to suppress evidence was heard by Robert L. Ullmann, J., in Superior Court. Eric Tennen for the defendant; Cailin M. Campbell (Jennifer J. Hickman also present) for the commonwealth; Mason A. Kortz, for Surveillance Technology Oversight Project, amicus curiae, submitted a brief; Brett Max Kaufman, Ashley Gorski and Patrick Toomey, of New York, Jennifer Granick, Jennifer Lynch and Andrew Crocker, of California, Matthew Spurlock, Matthew R. Segal, Jessie J. Rossman, Jessica J. Lewis, Nathan Freed Wessler and Joshua M. Daniels submitted a brief for American Civil Liberties Union and others, amici curiae (Docket No. SJC-13144) (April 1, 2022).

Click here to read the full text of the opinion.