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Use of Flock Cameras Is Not a Fourth Amendment "Search," District Court Rules

The first post-Chatrie ruling on the question.

|The Volokh Conspiracy |


For reasons explained in my draft article, The Fourth Amendment After Chatrie, there is good reason to believe that the Supreme Court's June ruling in Chatrie v. United States will trigger a rethinking of how the Fourth Amendment applies to automated license plate reader systems such as those provided by Flock Safety.  There was an oral argument in the Eleventh Circuit on this question on July 29 that you can listen to here, but there has been no ruling yet on that from the Eleventh Circuit.  Last week, however, the United States District Court for the Central District of California became the first court I'm aware of to weigh in on whether the use of Flock cameras is a Fourth Amendment search after Chatrie.

The new ruling, United States v. Riley, concludes that use of Flock cameras was not a search. In the case, police investigating two kidnappings queried the Flock cameras of two California cities, obtaining four photographs each of the whereabouts of the defendant's car.   According to the court, this was not enough of a privacy invasion to constitute a Fourth Amendment search:

The ALPR database searches used during the Culver City and Carson investigations are thus clearly distinguishable from and less extensive than the "near perfect surveillance" achievable through the historical CSLI at issue in Carpenter and the Google Location History data at issue in Chatrie. The ALPR data in this case could not create "an all-encompassing record" of Defendant's whereabouts. Carpenter, 585 U.S. at 311. And although some of Defendant's path in the Dodge Charge and Chevrolet Malibu may be inferred, there is no indication in the record that law enforcement could recreate the complete paths that Defendant traveled in those cars, even in combination with information from other sources, such that officers could create a "detailed log of [Defendant's] movements" from the data at issue here. Id. at 312. Nor did this surveillance provide the "intimate window" into Defendant's personal life that concerned the Supreme Court in Carpenter. Id. at 311. That is to say, the ALPR data did not reveal defendants "familial, political, professional, religious, and sexual associations." Id. Furthermore, the record does not show that the ALPR data here allows police to "reconstruct 'retrospective[ly],' and with no real effort, [Defendant's] comings and goings in any area. Chatrie, 146 S. Ct. at 2208 (alteration in original) (quoting Carpenter, 585 U.S. at 312).

For these reasons, the record here does not reveal a privacy threat analogous to the issues addressed in Carpenter and Chatrie. And it does not present "dragnet type law enforcement practices" constituting a Fourth Amendment search. United States v. Knotts, 460 U.S. 276, 284 (1983).

This is just a trial court decision, of course, and I assume it will be appealed to the court of appeals.  Other courts are considering the same question, and we don't know how they will rule.  But given the public interest in the issue, I thought I would flag the new opinion.  As always, stay tuned.