In his dissent in Carpenter v. United States, 138 S. Ct. 2206 (2018), Justice Kennedy observed that “the Cyber Age has vast potential both to expand and restrict individual freedoms in dimensions not contemplated in earlier times.” Justice Kennedy worried that the ruling, which held that a warrant is generally required for police to access cell site location information, would hamstring law enforcement by “transform[ing]” prior precedent into “an unprincipled and unworkable doctrine.” The Carpenter majority insisted, however, that its June 2018 decision was “a narrow one.” Future decisions will determine how far Carpenter will in fact reach, but recent decisions from the U.S. Courts of Appeals for the Second and Seventh Circuits demonstrate one important limit: the “good faith” exception to the exclusionary rule. While acknowledging Carpenter’s holding, both courts rejected the respective defendant-appellants’ appeals of suppression motion denials relating to searches predating Carpenter based on that exception.

Most recently, in United States v. Curtis, No. 17-1833, 2018 WL 4042631 (7th Cir. Aug. 24, 2018), the Seventh Circuit held that “even though it is now established that the Fourth Amendment requires a warrant for the type of cell-phone data present [t]here, exclusion of that information was not required because it was collected in good faith.” In Curtis, the appellant challenged the district court’s denial of his motion to suppress cell phone location information collected pursuant to the Stored Communications Act (SCA). Mr. Curtis did not dispute that the government had complied with the SCA, but argued he had a reasonable expectation of privacy in the location information and thus a search warrant was required. The district court denied the motion and permitted the location information to be offered as evidence, and Mr. Curtis was convicted of various crimes.

On appeal, the Seventh Circuit agreed that, per Carpenter, a warrant was required for the information, but that the Supreme Court “has not spoken to what should happen next.” According to the Curtis court, the answer was clear: the evidence did not have to be excluded because it was obtained in good-faith reliance on pre-Carpenter precedent.

Similarly, in United States v. Zodhiates, No. 17-839, 2018 WL 3977030 (2d Cir. Aug. 21, 2018), the appellant argued that the government violated the Fourth Amendment when it obtained his cell phone’s location information pursuant to an SCA subpoena. The Second Circuit recognized the importance of Carpenter but explained that when the government collected the information in 2011, precedent dictated that the government could obtain information revealed to a third party through a subpoena rather than with a warrant. Ultimately, because the government officials acted with “an objectively reasonable good-faith belief that their conduct is lawful,” the location information did not have to be excluded.

The good-faith exception to the exclusionary rule is not new, and the decisions in Curtis and Zodhiates indicate that it has staying power. The principle lives on in these decisions, alongside Carpenter’s holding that, in the future, a warrant generally will be necessary in circumstances like those presented in these cases. As a result, the good-faith exception will substantially limit Carpenter’s reach by cutting off challenges to cell phone location information collected prior to that decision. But while Carpenter’s effect on pending cases is necessarily limited, its full effect on new cases with arguably comparable facts remains to be seen. As the majority noted, it did “not begin to claim all the answers today,” and even beyond the good-faith exception, lower courts may heed the majority’s guidance to “tread carefully” in cases involving new technology and cabin Carpenter’s impact when considering future cases in different factual contexts.