UNIVERSITY OF THE DISTRICT OF - UDC Law Review

impermissibly intruded on that legitimate expectation.286
The Second Circuit’s conclusions on this issue were viewed as unsound, however, and have been rejected by all federal
circuits and district courts that have considered the canine home-sniff issue.287 Only one court has followed Thomas’s
privacy-based analysis and found that a canine home-sniff is a “search” under the Federal Constitution.288 The State v. Rabb
court, in reliance on Thomas and Kyllo’s concerns about protecting the privacy of the home from government intrusions,
explained:
Likewise, it is of no importance that a dog sniff provides limited information regarding only the presence or absence
of contraband, because as in Kyllo, the quality or quantity of information obtained through the search is not the feared
injury. Rather, it is the fact that law enforcement endeavored to obtain the information from inside the house at all, or
in this case, the fact that a dog’s sense of smell crossed the “firm line” of Fourth Amendment protections at the door
of [the] house.289
While federal courts, other than the Second Circuit, have refused to extend Fourth Amendment protection to canine homesniffs,
a number of states have interpreted their own constitutions to provide *889 protection under a variety of canine sniff
circumstances.290 Although not determinative of the Fourth Amendment search issue,291 these cases are strong evidence that
states routinely consider the circumstances of a canine sniff, and when privacy concerns are implicated, states provide
protection. In a sense, the sheer number of states that consider the circumstances of a canine sniff in determining whether it is
a “search” suggests that “time has set its face against” a categorical rule that sniffs are per se nonsearches.292 Further, these
states’ practice is evidence that the canine sniff technique can be viewed as a “search” when used in privacy-sensitive
circumstances without burdensome disruption of police investigative efforts. In view of the heightened expectation of privacy
associated with the home and the intrusiveness of bringing a drug-detection dog into the protected curtilage area of a private
residence, it is appropriate to characterize a canine home-sniff as a “search” under the Fourth Amendment.
*890 6. Reasonable Suspicion or Probable Cause
If the Court were to conclude that a canine home-sniff is, in fact, a “search” under the Fourth Amendment, as this Article
proposes, the essential remaining question would be what quantum of suspicion is required to support the practice: reasonable
suspicion or probable cause293 Certainly, the suspicion standard is an issue over which reasonable minds could disagree.
New York, Arizona, and Indiana, for example, have concluded that a canine home-sniff is a “search” under their state
constitutions but that reasonable suspicion is sufficient to support the sniff-search.294 On the other hand, Washington and
Ohio have interpreted their state constitutions to require a search warrant supported by probable cause.295 The Rabb court
also found the canine home-sniff to be a search but based its conclusion on the Fourth Amendment, which Rabb also
interpreted to require a warrant supported by probable cause.296 In view of the divergent approaches on the suspicion
standard, a few observations seem appropriate.
Absent exigent circumstances, a warrant is required to search a person’s home or person.297 While the Court has refused to
allow increased law enforcement efficiency to serve as a basis for bypassing *891 the warrant requirement,298 the Court does
consider the real-world pressures of law enforcement when police are asked to make split-second decisions involving
unfolding events in the field.299 In most cases involving canine home-sniffs, however, the police decision to perform the sniff
does not involve the sort of split-second calculation that was present in Terry. Similar to the use of a thermal imager, in most
cases there is time for police to resort to the warrant process.300 Some courts faced with the home-sniff question have
suggested that probable cause would be an illogical requirement because a showing of probable cause would allow officers to
obtain a search warrant to conduct a physical search of the premises in any event.301 While this argument may seem
intuitively plausible, it is incorrect. In fact, the same argument could be made for the thermal-imaging device at issue in
Kyllo: if police have probable cause to perform a thermal scan on a private home, then, the argument goes, police would also
have probable cause to physically search the home for contraband, thereby rendering the need for the thermal scan irrelevant.
The years since Kyllo have disproved this argument, however. The focus of post-Kyllo thermal-imaging warrant applications
has been on whether there is probable cause to conduct the scan, not on whether there is probable cause to physically search
the premises.302
*892 Similar to the thermal-imaging warrants required after Kyllo, a canine sniff of a private home should be supported by a
warrant issued on the basis of probable cause to perform the sniff, not probable cause to physically search the premises. The
requirement of a dog-sniff warrant would thereby ensure that canine sniffs of private residences would be limited to
circumstances in which police had conducted an investigation and established an objectively reasonable basis for performing
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