In 1967, the U.S. Supreme Court in Katz v. United States announced a series of exceptions to the Fourth Amendment’s warrant requirement. One of those exceptions is the “plain view” evidence exception; i.e., the police may seize items of contraband in “plain view” in a place in which they have a lawful presence.


Plain View Exception to Search Warrant


In 1990, the Supreme Court in Horton v. California established that the plain view doctrine has a two-prong test that must be satisfied before the plain view exception can be applied to evidence seized without a warrant: “First, not only must the item be in plain view; its incriminating character must also be immediately apparent. Second, not only must the officer be lawfully located in a place from which the object can be plainly seen, but he or she must also have a lawful right of access of the object itself.”


Plain Feel, Plain Smell, Plain Hearing???


The Katz decision spawned two other subsequent exceptions to the warrant requirement: plain feel (Minnesota v. Dickerson—1993) and plain smell (United States v. Place—1983). It should be noted that while the Supreme Court has never definitively recognized a plain smell exception as it has with the plain view exception, most federal circuits and state courts have given constitutional credence to the exception.


In pre-Katz decisions, the Supreme Court gave some constitutional credibility to at least two other exceptions: plain shape (Henry v. United States—1959) and plain hearing (Hoffa v. United States—1966).


Erosion of Warrant Requirement


All these exceptions, except perhaps the plain view exception, are disturbing because they severely erode the warrant requirement. Take, for example, the plain hearing exception. The Ninth Circuit Court of Appeals on September 7, 2016 issued an opinion that could dramatically alter this legal landscape.


In the case of United States v. Carey, the appeals court dealt with a wiretap case in which federal agents secured a wiretap order for a San Diego phone number. The order was for seven days. The federal agents believed the number was being used by Ignacio Escamilla Estrada (Escamilla) in connection with his drug smuggling and distribution conspiracy activities.


During the seven day monitoring period, the agents overheard a number of drug-related conversations before they realized that Escamilla was not using the phone. That fact notwithstanding, the agents continued the wiretap monitoring believing that the individuals using the phone were part of Escamilla’s drug operation.


Motion to Suppress by Defense


One of the people heard using the phone was Michael Carey who was subsequently indicted for conspiracy to distribute cocaine. Carey’s defense attorney moved immediately to have the evidence obtained from the wiretap suppressed because the government had not applied for a wiretap order against him or his co-conspirators as required by the Wiretap Act under 18 U.S.C. §§ 2510-22. The district court denied the motion.


On appeal, the Ninth Circuit held that it was embracing the “plain hearing” exception by holding that the police may use evidence unrelated to a targeted investigation if it is overheard through a valid wiretap order. In effect, the appeals court held that the Wiretap Act requirements of probable cause and necessity as to the speakers being monitored do not apply in in most plain hearing situations.


Agents Must Discontinue Monitoring When Speakers Outside Target Conspiracy


The appeals court, however, qualified its ruling somewhat by saying “ … agents must discontinue monitoring the wiretap once they know or reasonably should know that the phone calls involve speakers outside the target conspiracy.”


Because the district court had failed to determine “exactly when agents knew or should have known that the phone conversations they were hearing did not involve Escamilla and his coconspirators,” the appeals court remanded for a hearing to determine what evidence, if any, was lawfully obtained through plain hearing.


This kind of fact-based inquiry is subject to abuse. Federal agents will be permitted to enter a wiretap monitoring situation believing every voice they hear is part of their targeted investigation. They can compile a significant amount of evidence, as they did in the Carey case, before they have to say, “hold it, we’re investigating this and they’re talking about that.”


Plain Hearing Exception Flawed


The plain hearing test is as flawed as the plain smell test. Police not trained in detecting drug odors may be not able to distinguish the odor of marijuana from burning leaves. Likewise, police hearing conversations about drug trafficking can simply say that he or she thought the voice overheard was a target and the drugs they were talking about was connected to the investigation being monitored. There’s just too much wiggle room in the plain hearing test to suit us.