Fourth Amendment and advanced technology

Overview
State and federal courts have long since wrestled with whether and how to apply the Katz test to advancing technology. For example, the [[U.S. Supreme Court in Katz determined that when the suspect entered the phone booth and shut the door, he had a reasonable expectation of privacy in his being there. Thus, the police conducted an unreasonable search by using a listening and recording device without getting a warrant. Similarly, in Kyllo v. United States, the Court decided that a suspect had a reasonable expectation of privacy in his home when the police, suspecting him of growing marijuana, used a thermal imaging device without a warrant to detect the heat emanating from it. In contrast, when the Court was asked in United States v. Ciraolo to decide whether a suspect had a reasonable expectation of privacy in his 10-foot-high, fenced-in backyard after the police looked into it without a warrant from an airplane to see if he was growing marijuana, the Court concluded that he did not and that looking into the yard was not a search; thus, no warrant was necessary.

Likewise, the Court found that a defendant did not have a reasonable expectation of privacy in his car while traveling along public roads. In United States v. Knotts, Minnesota law enforcement officers placed (with the seller’s consent) a beeper in a chloroform container, believing that the defendant buyer was engaging in the production of illicit drugs. Officers subsequently followed the vehicle carrying the container, maintaining both a visual surveillance and a monitor receiving the beeper signals. Based on the beeper signals, the officers tracked the container to the defendant’s secluded cabin. After a three-day visual surveillance of the cabin, the officers obtained and executed a search warrant and found the container and a drug laboratory in the cabin. The defendant sought to have the evidence suppressed, arguing that the warrantless monitoring of the beeper violated the Fourth Amendment.

The Court disagreed and held that the officers’ actions did not constitute a search or seizure, as the defendant did not have a legitimate expectation of privacy because the beeper signal was not used to monitor movement of the container within a private residence. Instead, it was used to monitor movement along public highways and other areas visible to the naked eye.

However, in a similar scenario, when a beeper was activated while the suspect was inside his house, the Court held that the suspect did have a reasonable expectation of privacy in his home and that the absence of a warrant constituted an unreasonable search.45 In United States v. Karo,46 Drug Enforcement Administration (DEA) agents installed an electronic beeper in a can of ether with the consent of the owner (a government informant). The marked can was sold with others to the defendants, who intended to use the contents for cocaine production. Having tracked the can to several residences and storage facilities, law enforcement determined the can’s location and obtained an arrest warrant. The defendants were arrested and charged with possession of cocaine with intent to distribute. One of the defendants sought to have the evidence suppressed as “tainted fruit” of an unlawful search. This case presented two issues for the Court to address: (1) whether the beeper’s installation constituted a search or seizure when the container was delivered to a buyer without any knowledge of the beeper’s presence and (2) whether the beeper’s monitoring within an individual’s residence falls within the Fourth Amendment’s ambit when it reveals information that could not have been obtained through visual surveillance.

As to the first issue, the Court found that the defendant lacked a Fourth Amendment interest, as the owner’s consent was sufficient to withstand the challenge. However, the Court found that the Fourth Amendment was violated when the agents used the beeper to locate the container in a private dwelling without first obtaining a search warrant. Although the transfer of the beeper to the defendant did not violate the Fourth Amendment, the monitoring of the beeper in a private residence not open to visual surveillance did violate the Fourth Amendment.47