The Fourth Amendment has received significant attention in recent court rulings involving surveillance, electronic data retrieval, and other types of technology. Two rulings issued on October 21, 2019 demonstrate how difficult it can be to anticipate the outcome of Fourth Amendment disputes relating to technology. In one, the Georgia Supreme Court found the warrantless search of electronic data from a car following a fatal accident to be unconstitutional. In the second, the U.S. Court for the Western District of Tennessee held that the Fourth Amendment permitted the warrantless placement of a government surveillance camera on a man’s private hunting and fishing property.

Mobley v. State (Ga. Oct. 21, 2019)

In Mobley, the Georgia Supreme Court ruled that a trial court erred in denying a motion to suppress evidence that law enforcement retrieved from the electronic data recorder in the defendant’s car. In coming to this conclusion, the Mobley court ruled that – regardless of any reasonable expectation of privacy – the physical entry of a police officer into the defendant’s car to retrieve the electronic data was a search for Fourth Amendment purposes.

The Mobley case arose after a car driven by defendant Mobley collided with a car that pulled out of a private driveway; both occupants of the latter car died. Before the cars were removed from the accident scene, a police investigator entered both cars, and attached a crash data retrieval device to data ports in the cars to download available data. The data revealed that shortly before the collision, Mobley’s car was traveling almost 100 miles per hour. The next day, law enforcement applied for a warrant to seize the electronic data recorders. The warrant was issued, but no additional data was retrieved from the recorders. A grand jury indicted Mobley on a number of counts, including vehicular homicide.

Mobley moved to suppress evidence retrieved from the data recorder, arguing that it was an unreasonable search and seizure in violation of the Fourth Amendment. The trial court denied the motion, finding that because police obtained a warrant for the data the following day, and the warrant application did not rely on data from the device, that data would have “inevitably been discovered by investigators.”

Mobley appealed, and the Georgia Court of Appeals affirmed. The appeals court found Mobley had no reasonable expectation of privacy in the data, as much of it – such as approximate speed and whether a driver applied the brakes – could be observed by a person looking at the car based on speed reduction or brake light activation.

Last week, the Georgia Supreme Court reversed. Noting that the Fourth Amendment is concerned with government trespasses upon the rights of individuals to be secure in their “persons, houses, papers, and effects,” the court determined that the retrieval implicated Mobley’s Fourth Amendment rights, regardless of any reasonable expectation of privacy. The court pointed out that while the reasonable expectation of privacy inquiry established in Katz v. United States, 389 U.S. 347 (1967) is one way of determining whether the Fourth Amendment is implicated, that analysis did not replace the traditional trespass test. Because entering Mobley’s vehicle was trespassory in nature, the reasonable expectation of privacy inquiry was unnecessary.

Georgia’s highest court then concluded that because the data retrieval occurred without a warrant it was an unreasonable search and seizure that violated the Fourth Amendment. Also, because the record did not show the law enforcement officers were actively pursuing a warrant at the time the data was retrieved, the retrieval did not fit into the narrow “inevitable discovery” exception. Thus, the court held that the motion to suppress should have been granted.

In addition to re-affirming the vitality of the trespassory inquiry post-Katz, Mobley also demonstrates that adherence to criminal procedure must not take a back seat to the speed and convenience of digital data collection.

Hollingsworth v. United Sates Fish and Wildlife Service, et al. (W.D. Tenn. Oct. 21, 2019)

While Mobley may be hailed by privacy advocates, the Western District of Tennessee’s ruling in Hollingsworth is likely to be less enthusiastically embraced, despite being grounded in solid precedent. In Hollingsworth, the court dismissed constitutional claims against the U.S. Fish and Wildlife Service, an agent for the service, and an agent of Tennessee’s Wildlife Resources Agency based on a camera positioned on plaintiff Hollingsworth’s property to surveil him. The court found that the Fourth Amendment was not implicated because although the camera was on plaintiff’s property, it was in an “open field” rather than on the property surrounding plaintiff’s home.

The case arose after Hollingsworth found a camera mounted to a tree in the interior of property he used for hunting and fishing. Hollingsworth removed the camera and found pictures of men he believed to be the defendants on the SD card it contained. Hollingsworth sued the individual agents and their respective agencies for Fourth Amendment violations and trespass, although the claim against the state wildlife agency was dismissed on sovereign immunity grounds. The remaining defendants moved to dismiss.

The court observed that while the Fourth Amendment protects “houses” against unreasonable searches, that protection extends only to the dwelling and the surrounding land (known as the curtilage) where “privacy expectations are most heightened.” However, the Fourth Amendment does not prohibit all investigations on private property, such as in those areas which are more easily accessible to the public and less intimate to one’s home. Such areas beyond the curtilage are considered “open field,” and intrusion upon those areas is not considered a search of one’s house.

As a result, the court found that even though Hollingsworth found the camera in a position designed to record his entrance and exit from his property, and even though his property was posted and landlocked by other parcels, the use of the camera did not constitute a Fourth Amendment violation. This was true even where the defendants had to commit a trespass to reach the area where they placed the camera, because the Fourth Amendment protects a smaller scope of property than trespass law does. The court also explained that prior cases had held that areas outside of the curtilage still could be considered “open field” despite efforts to prevent unwanted guests from intruding, such as the use of fences, locked gates, and “no trespassing” signs. Further, the court explained that a reasonable expectation of privacy analysis was unnecessary, because courts have consistently held that individuals cannot have such an expectation in open field property. Finally, the court dispatched with Hollingsworth’s argument that the use of a surveillance camera to observe his movements was analogous to the GPS tracking of a person’s movements addressed in U.S. v. Jones, 565 U.S. 400 (2012), because the Jones holding relied on the determination that a car was an “effect” for Fourth Amendment purposes and thus in the zone of constitutional privacy, whereas an open field is not.


Although it may seem illogical that the Fourth Amendment would tolerate the warrantless placement of a surveillance camera on an individual’s property but not the use of information for which a warrant was obtained the next day, both decisions are grounded in long-standing precedent. Although neither vehicle data recorders nor surveillance cameras existed at the time the Fourth Amendment was drafted, the trespassory inquiry and open field doctrine are both sufficiently developed to adequately address new technology. Technological developments can pose issues where the law is ill-suited to adapt to novel issues, but for now, it appears that Fourth Amendment jurisprudence is flexible enough to tackle changing circumstances. However, had Hollingsworth involved, for example, a highly powerful zoom lens or drone, the argument against applying the open field doctrine might have been stronger.