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The Carpenter Court held that warrantless access to seven or more days of cell site location information (CSLI) constitutes a violation of the reasonable expectation of privacy that individuals have in the whole of their physical movements. But the grounds on which the Court drew a line characterize all sorts of digital records—including those at issue in Miller and Smith, belying the majority’s claim that the decision leaves third-party doctrine intact. Instead of avoiding Katz’s pitfalls, moreover, the Court emphasized voluntary assumption of risk, doubling down on the subjective nature of judicial determination. The decision will likely lead to further chaos and fragmentation. To take account of the significant challenges ahead, this article proposes that, going forward, courts eschew voluntary assumption of risk. An outgrowth of open space and informant doctrines, the approach imported analogical fallacies into the Court’s jurisprudence and ignored the implications of new technologies. Instead, the Court should return to a property-based approach and extend the rule of functional equivalence, which already characterizes home and border searches, to digital papers. In ascertaining who owns digital documents and records, the Court can employ a but for analysis, asking whether the material would exist but for the right-holder’s actions. To determine whether, by providing access to information, the right-holders divest themselves of their ownership interest in the data, as Justice Gorsuch recognized in Carpenter, the law of bailment and positive law can play a crucial role. English common law has long recognized that possession is insufficient to extinguish a property owner’s residual rights. The approach advocated has the advantage of clarity, adaptation to the modern world, and the restoration of core Fourth Amendment rights protected at the founding.

Publication Citation

Supreme Court Review, Vol. 2018, Pp. 347-410.