Supreme Court of the United States
UNITED STATES, Petitioner,
v.
James Connors KARO et al.
Decided July 3, 1984.
468 U.S. 705
Justice WHITE delivered the opinion of the Court.
In United States v. Knotts, 460 U.S. 276, 103 S.Ct. 1081, 75 L.Ed.2d 55 (1983), we held that the warrantless
monitoring of an electronic tracking device (“beeper”) inside a container of chemicals did not violate the Fourth
Amendment when it revealed no information that could not have been obtained through visual surveillance. In this
case, we are called upon to address two questions left unresolved in Knotts: (1) whether installation of a beeper in a
container of chemicals with the consent of the original owner constitutes a search or seizure within the meaning of the
Fourth Amendment when the container is delivered to a buyer having no knowledge of the presence of the beeper, and
(2) whether monitoring of a beeper falls within the ambit of the Fourth Amendment when it reveals information that
could not have been obtained through visual surveillance.
I
In August 1980 Agent Rottinger of the Drug Enforcement Administration (DEA) learned that respondents James
Karo, Richard Horton, and William Harley had ordered 50 gallons of ether from Government informant Carl Muehlenweg of Graphic Photo Design in Albuquerque, N.M. Muehlenweg told Rottinger that the ether was to be used to
extract cocaine from clothing that had been imported into the United States. The Government obtained a court order
authorizing the installation and monitoring of a beeper in one of the cans of ether. With Muehlenweg's consent, agents
substituted their own can containing a beeper for one of the cans in the shipment and then had all 10 cans painted to
give them a uniform appearance.
On September 20, 1980, agents saw Karo pick up the ether from Muehlenweg. They then followed Karo to his
house using visual and beeper surveillance. At one point later that day, agents determined by using the beeper that the
ether was still inside the house, but they later determined that it had been moved undetected to Horton's house, where
they located it using the beeper. Agent Rottinger could smell the ether from the public sidewalk near Horton's residence. Two days later, agents discovered that the ether had once again been moved, and, using the beeper, they located
it at the residence of Horton's father. The next day, the beeper was no longer transmitting from Horton's father's house,
and agents traced the beeper to a commercial storage facility.
Because the beeper equipment was not sensitive enough to allow agents to learn precisely which locker the ether
was in, agents obtained a subpoena for the records of the storage company and learned that locker 143 had been rented
by Horton. Using the beeper, agents confirmed that the ether was indeed in one of the lockers in the row containing
locker 143, and using their noses they detected the odor of ether emanating from locker 143. On October 8 agents
obtained an order authorizing installation of an entry tone alarm into the door jamb of the locker so they would be able
to tell when the door was opened. While installing the alarm, agents observed that the cans containing ether were still
inside. Agents ceased visual and beeper surveillance, relying instead on the entry tone alarm. However, on October 16
Horton retrieved the contents from the locker without sounding the alarm. Agents did not learn of the entry until the
manager of the storage facility notified them that Horton had been there.
Using the beeper, agents traced the beeper can to another self-storage facility three days later. Agents detected the
smell of ether coming from locker 15 and learned from the manager that Horton and Harley had rented that locker
using an alias the same day that the ether had been removed from the first storage facility. The agents obtained an order
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authorizing the installation of an entry tone alarm in locker 15, but instead of installing that alarm, they obtained
consent from the manager of the facility to install a closed-circuit video camera in a locker that had a view of locker
15. On February 6, 1981, agents observed, by means of the video camera, Gene Rhodes and an unidentified woman
removing the cans from the locker and loading them onto the rear bed of Horton's pickup truck. Using both visual and
beeper surveillance agents tracked the truck to Rhodes' residence where it was parked in the driveway. Agents then
observed Rhodes and a woman bringing boxes and other items from inside the house and loading the items into the
trunk of an automobile. Agents did not see any cans being transferred from the pickup.
At about 6 p.m. on February 6, the car and the pickup left the driveway and traveled along public highways to
Taos. During the trip, the two vehicles were under both physical and electronic surveillance. When the vehicles arrived at a house in Taos rented by Horton, Harley, and Michael Steele, the agents did not maintain tight surveillance
for fear of detection. When the vehicles left the Taos residence, agents determined, using the beeper monitor that the
beeper can was still inside the house. Again on February 7, the beeper revealed that the ether can was still on the
premises. At one point, agents noticed that the windows of the house were wide open on a cold windy day, leading
them to suspect that the ether was being used. On February 8, the agents applied for and obtained a warrant to search
the Taos residence based in part on information derived through use of the beeper. The warrant was executed on
February 10, 1981, and Horton, Harley, Steele, and Evan Roth were arrested, and cocaine and laboratory equipment
were seized.
Respondents Karo, Horton, Harley, Steele, and Roth were indicted for conspiring to possess cocaine with intent to
distribute it and with the underlying offense. 21 U.S.C. §§ 841(a)(1) and 846. * * * The District Court granted respondents' pretrial motion to suppress the evidence seized from the Taos residence on the grounds that the initial
warrant to install the beeper was invalid and that the Taos seizure was the tainted fruit of an unauthorized installation
and monitoring of that beeper. The Court of Appeals affirmed, except with respect to Rhodes, holding that a warrant
was required to install the beeper in one of the 10 cans of ether and to monitor it in private dwellings and storage
lockers. 710 F.2d 1433 (CA10 1983). The warrant for the search in Taos and the resulting seizure were tainted by the
prior illegal conduct of the Government. The evidence was therefore properly suppressed with respect to respondents
Horton, Harley, Steele, and Roth, who were held to have protectible interests in the privacy of the Taos dwelling, and
with respect to respondent Karo because the beeper had been installed without a warrant and had been monitored
while its ether-can host was in his house. We granted the Government's petition for certiorari. * * *
II
Because the judgment below in favor of Karo rested in major part on the conclusion that the installation violated
his Fourth Amendment rights and that any information obtained from monitoring the beeper was tainted by the initial
illegality, we must deal with the legality of the warrantless installation. It is clear that the actual placement of the
beeper into the can violated no one's Fourth Amendment rights. The can into which the beeper was placed belonged at
the time to the DEA, and by no stretch of the imagination could it be said that respondents then had any legitimate
expectation of privacy in it. The ether and the original 10 cans, on the other hand, belonged to, and were in the possession of, Muehlenweg, who had given his consent to any invasion of those items that occurred. Thus, even if there
had been no substitution of cans and the agents had placed the beeper into one of the original 10 cans, Muehlenweg's
consent was sufficient to validate the placement of the beeper in the can. See United States v. Matlock, 415 U.S. 164,
94 S.Ct. 988, 39 L.Ed.2d 242 (1974); Frazier v. Cupp, 394 U.S. 731, 89 S.Ct. 1420, 22 L.Ed.2d 684 (1969).
The Court of Appeals acknowledged that before Karo took control of the ether “the DEA and Muehlenweg
presumably could do with the can and ether whatever they liked without violating Karo's rights.” 710 F.2d, at 1438. It
did not hold that the actual placement of the beeper into the ether can violated the Fourth Amendment. Instead, it held
that the violation occurred at the time the beeper-laden can was transferred to Karo. The court stated:
“All individuals have a legitimate expectation of privacy that objects coming into their rightful ownership do not
have electronic devices attached to them, devices that would give law enforcement agents the opportunity to monitor
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the location of the objects at all times and in every place that the objects are taken, including inside private residences
and other areas where the right to be free from warrantless governmental intrusion is unquestioned.” Ibid.
Not surprisingly, the Court of Appeals did not describe the transfer as either a “search” or a “seizure,” for plainly
it is neither. A “search” occurs “when an expectation of privacy that society is prepared to consider reasonable is
infringed.” United States v. Jacobsen, 466 U.S. 109, 113, 104 S.Ct. 1652, 1656, 80 L.Ed.2d 85 (1984). The mere
transfer to Karo of a can containing an unmonitored beeper infringed no privacy interest. It conveyed no information
that Karo wished to keep private, for it conveyed no information at all. To be sure, it created a potential for an invasion
of privacy, but we have never held that potential, as opposed to actual, invasions of privacy constitute searches for
purposes of the Fourth Amendment. A holding to that effect would mean that a policeman walking down the street
carrying a parabolic microphone capable of picking up conversations in nearby homes would be engaging in a search
even if the microphone were not turned on. It is the exploitation of technological advances that implicates the Fourth
Amendment, not their mere existence.
We likewise do not believe that the transfer of the container constituted a seizure. A “seizure” of property occurs
when “there is some meaningful interference with an individual's possessory interests in that property.” Ibid. Although
the can may have contained an unknown and unwanted foreign object, it cannot be said that anyone's possessory
interest was interfered with in a meaningful way. At most, there was a technical trespass on the space occupied by the
beeper. The existence of a physical trespass is only marginally relevant to the question of whether the Fourth
Amendment has been violated, however, for an actual trespass is neither necessary nor sufficient to establish a constitutional violation. Compare Katz v. United States, 389 U.S. 347, 88 S.Ct. 507, 19 L.Ed.2d 576 (1967) (no trespass,
but Fourth Amendment violation), with Oliver v. United States, 466 U.S. 170, 104 S.Ct. 1735, 80 L.Ed.2d 214 (1984)
(trespass, but no Fourth Amendment violation). Of course, if the presence of a beeper in the can constituted a seizure
merely because of its occupation of space, it would follow that the presence of any object, regardless of its nature,
would violate the Fourth Amendment.
We conclude that no Fourth Amendment interest of Karo or of any other respondent was infringed by the installation of the beeper. Rather, any impairment of their privacy interests that may have occurred was occasioned by
the monitoring of the beeper.FN3
FN3. Despite this holding, warrants for the installation and monitoring of a beeper will obviously be desirable
since it may be useful, even critical, to monitor the beeper to determine that it is actually located in a place not
open to visual surveillance. As will be evident below, such monitoring without a warrant may violate the
Fourth Amendment.
III
In United States v. Knotts, 460 U.S. 276, 103 S.Ct. 1081, 75 L.Ed.2d 55 (1983), law enforcement officials, with
the consent of the seller, installed a beeper in a 5–gallon can of chloroform and monitored the beeper after delivery of
the can to the buyer in Minneapolis, Minn. Although there was partial visual surveillance as the automobile containing
the can moved along the public highways, the beeper enabled the officers to locate the can in the area of a cabin near
Shell Lake, Wis., and it was this information that provided the basis for the issuance of a search warrant. As the case
came to us, the installation of the beeper was not challenged; only the monitoring was at issue. The Court held that
since the movements of the automobile and the arrival of the can containing the beeper in the area of the cabin could
have been observed by the naked eye, no Fourth Amendment violation was committed by monitoring the beeper
during the trip to the cabin. In Knotts, the record did not show that the beeper was monitored while the can containing
it was inside the cabin, and we therefore had no occasion to consider whether a constitutional violation would have
occurred had the fact been otherwise.
Here, there is no gainsaying that the beeper was used to locate the ether in a specific house in Taos, N.M., and that
that information was in turn used to secure a warrant for the search of the house. The affidavit supporting the application for a search warrant recited that the ether arrived at the residence in a motor vehicle that later departed and that:
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“For fear of detection, we did not maintain tight surveillance of the residence.... Using the ‘beeper’ locator, I
positively determined that the ‘beeper’ can (5–gallon can of ether, described earlier in this affidavit) was now inside
the above-described premises to be searched because the ‘beeper’ locator (direction finder) pinpointed the beeper
signal as emanating from the above-described premises.... Again, later on Saturday (now in the daytime), 7 February
1981, my ‘beeper’ locator still shows a strong ‘beeper’ signal emanating from inside the above-described residence.”
App. 57–58.
This case thus presents the question whether the monitoring of a beeper in a private residence, a location not open
to visual surveillance, violates the Fourth Amendment rights of those who have a justifiable interest in the privacy of
the residence. Contrary to the submission of the United States, we think that it does.
At the risk of belaboring the obvious, private residences are places in which the individual normally expects
privacy free of governmental intrusion not authorized by a warrant, and that expectation is plainly one that society is
prepared to recognize as justifiable. Our cases have not deviated from this basic Fourth Amendment principle.
Searches and seizures inside a home without a warrant are presumptively unreasonable absent exigent circumstances. Welsh v. Wisconsin, 466 U.S. 740, 748–749, 104 S.Ct. 2091, 2097, 80 L.Ed.2d 732 (1984); Steagald v. United
States, 451 U.S. 204, 211–212, 101 S.Ct. 1642, 1647–1648, 68 L.Ed.2d 38 (1981); Payton v. New York, 445 U.S. 573,
586, 100 S.Ct. 1371, 1380, 63 L.Ed.2d 639 (1980). In this case, had a DEA agent thought it useful to enter the Taos
residence to verify that the ether was actually in the house and had he done so surreptitiously and without a warrant,
there is little doubt that he would have engaged in an unreasonable search within the meaning of the Fourth
Amendment. For purposes of the Amendment, the result is the same where, without a warrant, the Government surreptitiously employs an electronic device to obtain information that it could not have obtained by observation from
outside the curtilage of the house. The beeper tells the agent that a particular article is actually located at a particular
time in the private residence and is in the possession of the person or persons whose residence is being watched. Even
if visual surveillance has revealed that the article to which the beeper is attached has entered the house, the later
monitoring not only verifies the officers' observations but also establishes that the article remains on the premises.
Here, for example, the beeper was monitored for a significant period after the arrival of the ether in Taos and before the
application for a warrant to search.
The monitoring of an electronic device such as a beeper is, of course, less intrusive than a full-scale search, but it
does reveal a critical fact about the interior of the premises that the Government is extremely interested in knowing and
that it could not have otherwise obtained without a warrant. The case is thus not like Knotts, for there the beeper told
the authorities nothing about the interior of Knotts' cabin. The information obtained in Knotts was “voluntarily conveyed to anyone who wanted to look ...,” 460 U.S., at 281, 103 S.Ct., at 1085; here, as we have said, the monitoring
indicated that the beeper was inside the house, a fact that could not have been visually verified.
We cannot accept the Government's contention that it should be completely free from the constraints of the Fourth
Amendment to determine by means of an electronic device, without a warrant and without probable cause or reasonable suspicion, whether a particular article—or a person, for that matter—is in an individual's home at a particular
time. Indiscriminate monitoring of property that has been withdrawn from public view would present far too serious a
threat to privacy interests in the home to escape entirely some sort of Fourth Amendment oversight.
We also reject the Government's contention that it should be able to monitor beepers in private residences without
a warrant if there is the requisite justification in the facts for believing that a crime is being or will be committed and
that monitoring the beeper wherever it goes is likely to produce evidence of criminal activity. Warrantless searches are
presumptively unreasonable, though the Court has recognized a few limited exceptions to this general rule. See, e.g.,
United States v. Ross, 456 U.S. 798, 102 S.Ct. 2157, 72 L.Ed.2d 572 (1982) (automobiles); Schneckloth v.
Bustamonte, 412 U.S. 218, 93 S.Ct. 2041, 36 L.Ed.2d 854 (1973) (consent); Warden v. Hayden, 387 U.S. 294, 87
S.Ct. 1642, 18 L.Ed.2d 782 (1967) (exigent circumstances). The Government's contention that warrantless beeper
searches should be deemed reasonable is based upon its deprecation of the benefits and exaggeration of the difficulties
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associated with procurement of a warrant. The Government argues that the traditional justifications for the warrant
requirement are inapplicable in beeper cases, but to a large extent that argument is based upon the contention, rejected
above, that the beeper constitutes only a minuscule intrusion on protected privacy interests. The primary reason for the
warrant requirement is to interpose a “neutral and detached magistrate” between the citizen and “the officer engaged in
the often competitive enterprise of ferreting out crime.” Johnson v. United States, 333 U.S. 10, 14, 68 S.Ct. 367, 369,
92 L.Ed. 436 (1948). Those suspected of drug offenses are no less entitled to that protection than those suspected of
nondrug offenses. Requiring a warrant will have the salutary effect of ensuring that use of beepers is not abused, by
imposing upon agents the requirement that they demonstrate in advance their justification for the desired search. This
is not to say that there are no exceptions to the warrant rule, because if truly exigent circumstances exist no warrant is
required under general Fourth Amendment principles.
If agents are required to obtain warrants prior to monitoring a beeper when it has been withdrawn from public
view, the Government argues, for all practical purposes they will be forced to obtain warrants in every case in which
they seek to use a beeper, because they have no way of knowing in advance whether the beeper will be transmitting its
signals from inside private premises. The argument that a warrant requirement would oblige the Government to obtain
warrants in a large number of cases is hardly a compelling argument against the requirement. It is worthy of note that,
in any event, this is not a particularly attractive case in which to argue that it is impractical to obtain a warrant, since a
warrant was in fact obtained in this case, seemingly on probable cause. * * *
In sum, we discern no reason for deviating from the general rule that a search of a house should be conducted
pursuant to a warrant.
***
The judgment of the Court of Appeals is accordingly
Reversed.
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