Rehearing Denied July 01, 2019
[Copyrighted Material Omitted]
Certiorari to the Colorado Court of Appeals, Court of Appeals
Case No. 16CA50
for Petitioner: Philip J. Weiser, Attorney General, Paul
Koehler, First Assistant Attorney General, Denver, Colorado
Attorneys for Respondent: Megan A. Ring, Public Defender,
John Plimpton, Deputy Public Defender, Denver, Colorado
Inside defendant Kevin McKnights truck, police officers
discovered a pipe containing what later proved to be
methamphetamine residue. That discovery culminated in
McKnights conviction for certain drug offenses. On appeal,
he challenged the constitutionality of the search that
revealed the pipe.
A division of the court of appeals reversed McKnights
convictions. People v. McKnight, 2017 COA 93, ¶ 25,
__ P.3d __. Each member of the division wrote separately,
wrestling with what effect, if any, legalized marijuana in
Colorado should have on the constitutionality of the search
of McKnights truck. To which you might say, but this is a
methamphetamine case. So, why are we talking about marijuana?
Well, the drug-detection dog used to find the pipe, Kilo, was
trained to alert on multiple drugs, including marijuana. Even
a hint of marijuana can trigger the same response from Kilo
as any quantity of methamphetamine.
And thats where things get tricky. After all, the possession
of an ounce or less of marijuana by someone twenty-one or
older is legal in Colorado, following the passage of
Amendment 64, Colo. Const. art. XVIII, § 16(3), even though
such possession remains illegal under federal law. Thus, no
matter how reliable his nose, Kilo can now render a kind of
false positive for marijuana. He has been trained to alert to
marijuana based on the notion that marijuana is always
contraband, when that is no longer true under state law. And
historically, whether a drug-detection dog might alert on
noncontraband drives whether the dogs sniff constitutes a
search implicating constitutional protections. The dogs
sniff arguably intrudes on a persons reasonable expectation
of privacy in lawful activity. If so, that intrusion must be
justified by some degree of particularized suspicion of
Does this mean that Amendment 64 gave McKnight a reasonable
expectation of privacy under either the federal or state
constitution that was violated by Kilos keen sense of smell?
McKnight says yes. Among other things, he claims that the
Colorado Constitution prohibited Kilos intrusion without at
least reasonable suspicion that McKnight had committed or was
committing a crime. Because there was none, McKnight asserts
that the trial court should have suppressed the pipe. Two
members of the division agreed. McKnight, ¶ 3.
And even if the "sniff [was] up to snuff" (to use
Justice Kagans popular shorthand from a slightly different
context in Florida v. Harris, 568 U.S. 237, 248, 133
S.Ct. 1050, 185 L.Ed.2d 61 (2013)), McKnight further argued
that there was no probable cause for the post-sniff hand
search of his truck that revealed the pipe. Again, because of
Amendment 64, two members of the division agreed. McKnight, ¶
The People counter that, despite Amendment 64, marijuana
remains contraband in many circumstances at the state level,
and illegal under all circumstances federally, and thus
Kilos sniff was not a search requiring so much as reasonable
suspicion. The People further contend that an alert from a
dog trained to detect marijuana, in
addition to other substances, still provides probable cause
justifying a search.
We hold that a sniff from a drug-detection dog that is
trained to alert to marijuana constitutes a search under
article II, section 7 of the Colorado Constitution because
that sniff can detect lawful activity, namely the legal
possession of up to one ounce of marijuana by adults
twenty-one and older. We further hold that, in Colorado, law
enforcement officers must have probable cause to believe that
an item or area contains a drug in violation of state law
before deploying a drug-detection dog that alerts to
marijuana for an exploratory sniff. Because there was no such
probable cause justifying Kilos search of McKnights truck,
the trial court erred in denying McKnights motion to
Accordingly, we affirm the judgment of the court of appeals.
I. Facts and Procedural History
Evidence presented at a suppression hearing established the
While on patrol in an unmarked police vehicle one night in
February 2015, Craig Police Officer Bryan Gonzales observed a
parked pickup truck facing the wrong way in a one-way alley
near an apartment complex. A man stood outside of the
passenger-side door of the truck. Although Officer Gonzales
saw no behavior consistent with an exchange or transaction,
he followed the truck as it traveled a few blocks. The truck
then parked in front of a residence where police had found
drugs almost two months earlier, and it remained parked there
for approximately fifteen minutes. During that time, no one
exited the truck or the residence. When the truck started
moving again, Gonzales trailed along.
When the driver of the truck failed to signal a turn,
Gonzales pulled the truck over. He discovered that McKnight
was the driver. And Gonzales recognized the passenger as
someone who had used methamphetamine "at some point in
the past," but he wasnt sure how recently.
During the traffic stop, Gonzales asked Sergeant Courtland
Folks of the Moffat County Sheriffs Office to respond with
his drug-detection dog, Kilo, who had been trained to detect
the odors of marijuana, methamphetamine, cocaine, heroin, and
ecstasy. If Kilo detects the scent of any one of those
substances, he should alert. And he exhibits the same alert
for all five drugs.
Within five minutes of the stop, Kilo was on the job. As
Folks walked Kilo around McKnights truck, Folks asked
McKnight if he had "any narcotics on him." McKnight
said no. Kilo quickly "alerted" on the drivers
door beneath the drivers open window. This means that Kilo
engaged in a rapid sniffing pattern and behaved in a manner
suggesting the presence of one of the substances on which he
had been trained. According to Folks, Kilo then "put his
nose on the drivers door, back to the door handle, did a
purge, which means he cleared his nose, took another deep
breath and immediately started giving a trained indication,
which was barking."
The officers then ordered McKnight and the passenger to exit
the truck. After they complied, the officers patted them down
and found nothing on them. The officers then searched the
truck by hand. In a storage compartment under the rear seat,
they found a pipe containing suspected methamphetamine
Before trial, the defense moved to suppress the pipe, arguing
that it was the fruit of an unconstitutional search.
Specifically, McKnight argued that because marijuana is legal
in Colorado and Kilo was trained to detect marijuana, Kilos
sniff was a search that required particularized suspicion of
criminal activity before Kilo could be deployed, and there
was no such suspicion on these facts. Moreover, he contended
that Kilos alert did not provide probable cause for a
full-blown, human search of the truck. Through counsel,
McKnight grounded his arguments in the search and seizure
clauses of both the United States and Colorado Constitutions.
After a hearing, the trial court denied the motion to
suppress. In relevant part, the trial court noted that the
possession of marijuana remains illegal under many
circumstances in Colorado and is categorically illegal
under federal law. Without explicitly stating as much, the
trial court seemed to reason that a sniff by a dog trained to
detect marijuana does not constitute a search. And even if
Kilos sniff was a search, the trial court went on to
conclude that there was reasonable suspicion of criminal
activity supporting the search. With ample record support,
the court also concluded that Kilo reliably sniffs out the
drugs on which hes been trained. The trial court did not
address whether there was probable cause for the officers
hand search of the truck.
A jury later convicted McKnight of possession of a controlled
substance and possession of drug paraphernalia.
McKnight appealed. In three separate but partially
overlapping opinions, the court of appeals unanimously agreed
that the trial court erred in denying McKnights motion to
suppress the pipe and that the error was not harmless.
Therefore, the division reversed McKnights convictions.
• Judge Dailey, writing for himself and Judge Berger,
agreed with McKnight that, under the Colorado Constitution
after the enactment of Amendment 64, Kilos sniff was a
search requiring reasonable suspicion of criminal activity.
McKnight, ¶ 18 ("Because a dog sniff of a vehicle could
infringe upon a legitimate expectation of privacy solely
under state law, that dog sniff should now be considered a
search for purposes of article II section 7 of the state
constitution where the occupants are twenty-one years or
older."). Judge Dailey further determined that the
reasonable suspicion standard should govern, and he concluded
that the totality of the circumstances did not give the
police reasonable suspicion that McKnight had engaged in
criminal activity. Id. at ¶¶ 19-20, 22-24.
• Judge Jones, writing for himself and Judge Berger,
agreed with McKnight that Kilos alert, even in combination
with other circumstances, did not give the police probable
cause to conduct a warrantless hand search of McKnights
truck. Id. at ¶¶ 49-54 (Jones, J., specially
concurring). In doing so, Judge Jones sidestepped the issue
of whether Kilos sniff now constitutes a search under state
law. Id. at ¶ 37.
• Judge Berger, writing for himself, explained how a
person could have an enforceable expectation of privacy in
the possession of marijuana under state law, even in the face
of a federal prohibition. First, he noted that Colorado
courts must give effect to Colorado voters enactment of
Amendment 64. Id. at ¶ 29 (Berger, J., specially
concurring). Second, he observed that the People have not
argued that Amendment 64 is preempted by federal law.
Id. Finally, he concluded that when Amendment 64
legalized possession of up to one ounce of marijuana for
personal use by persons twenty-one years of age or older, it
also limited police authority to enforce the federal
prohibition. Id. at ¶ 31.
The People filed a petition for a writ of certiorari, and we
agreed to review the case.
After identifying the standard of review, we examine the
parallel evolution of federal and state jurisprudence
concerning police use of drug-detection dogs. We review
long-standing law reasoning that a sniff is not a search
because an individual has no legitimate expectation of
privacy as to contraband. But after the passage of Amendment
64, possession of an ounce or less of marijuana by someone
twenty-one or older is legal, and thus, marijuana is no
longer always "contraband" under state law. Because
Kilos sniff could detect lawful activity, we conclude his
sniff was a search under the Colorado Constitution. We then
what level of suspicion would justify deploying such a dog to
sniff a vehicle, ultimately concluding that, because the
sniff is a search, there must be probable cause to believe a
vehicle contains illegal narcotics under state law before
deploying a drug-detection dog trained to alert to marijuana.
We conclude that, under the totality of the circumstances,
there was no probable cause justifying the use of Kilo to
sniff McKnights truck or the subsequent hand search of the
truck, and, exclusion of the pipe is the appropriate remedy
for this violation of the Colorado Constitution.
A. Standard of Review
When reviewing a suppression order, we defer to the trial
courts factual findings if the record supports them, but we
review de novo the courts legal conclusions. Grassi v.
People, 2014 CO 12, ¶ 11, 320 P.3d 332, 335. So, we
address the constitutionality of Kilos sniff and the
subsequent hand search of the truck de novo.
B. Federal Law Governing Searches and Drug-Detection
The Fourth Amendment to the United States Constitution
The right of the people to be secure in their persons,
houses, papers, and effects, against unreasonable searches
and seizures, shall not be violated, and no Warrants shall
issue, but upon probable cause, supported by Oath or
affirmation, and particularly describing the place to be
searched, and the persons or things to be seized.
"protects people, not places" from unreasonable
governmental searches and seizures. Katz v. United
States, 389 U.S. 347, 351, 88 S.Ct. 507, 19 L.Ed.2d 576
(1967); see also U.S. Const. amend. IV. A search in
the constitutional sense occurs "when the government
violates a subjective expectation of privacy that society
recognizes as reasonable." Kyllo v. United
States, 533 U.S. 27, 33, 121 S.Ct. 2038, 150 L.Ed.2d 94
(2001) (citing Katz, 389 U.S. at 361, 88 S.Ct. 507
(Harlan, J., concurring)).
"Warrantless searches are presumptively
unreasonable," and thus unconstitutional, unless an
exception to the warrant requirement exists. United
States v. Karo, 468 U.S. 705, 717, 104 S.Ct. 3296, 82
L.Ed.2d 530 (1984). Courts measure the constitutionality of a
search (either pursuant to a warrant or warrantless) at the
time a search is performed. The Fourth Amendment does not
favor post hoc justifications based on what was found during
a search. See, e.g., People v. Sotelo, 2014
CO 74, 336 P.3d 188 ("[C]ourts may not use the benefit
of hindsight in evaluating application of the Fourth
Amendment."); see also California v.
Acevedo, 500 U.S. 565, 599, 111 S.Ct. 1982, 114 L.Ed.2d
619 (1991) (Stevens, J., dissenting) ("Neither evidence
uncovered in the course of a search nor the scope of the
search conducted can be used to provide post hoc
justification for a search unsupported by probable cause at
its inception."); United States v. Montoya de
Hernandez, 473 U.S. 531, 559, 105 S.Ct. 3304, 87 L.Ed.2d
381 (1985) (Brennan, J., dissenting) ("[P]ost hoc
rationalizations have no place in our Fourth Amendment
jurisprudence, which demands that we prevent hindsight from
coloring the evaluation of the reasonableness of a search or
seizure. " (quoting United States v.
Martinez-Fuerta, 428 U.S. 543, 565, 96 S.Ct. 3074, 49
L.Ed.2d 1116 (1976))).
A warrantless search may be constitutional if there was
probable cause to believe the place or item to be searched
contained contraband or evidence of a crime, and the
circumstances met an exception to the warrant requirement.
One such exception is the automobile exception. Beginning
with Carroll v. United States, the Supreme Court has
reasoned that automobiles warrant a lesser degree of privacy
than that afforded to homes because of a vehicles
"ready" mobility, the existing, pervasive
government regulation of cars, and the low probability that a
car is used to store personal effects. See 267 U.S.
132, 153, 45 S.Ct. 280, 69 L.Ed. 543 (1925) (reasoning that
there is "a necessary difference between a search of a
store, dwelling house, or other structure ... [where] a
proper official warrant readily may be obtained and a search
of a ship, motor boat, wagon, or automobile ... where it is
not practicable to secure a warrant, because the
vehicle can be quickly moved"). Nearly a century later,
the law remains the same: If an officer has lawfully stopped
a vehicle, and has probable cause to believe the vehicle
contains evidence of a crime, then the officer may conduct a
search of the car without first obtaining a warrant.
Collins v. Virginia, __ U.S. __, 138 S.Ct. 1663,
1670, 201 L.Ed.2d 9 (2018).
As the Supreme Court continued to embrace and refine the
automobile exception, drug-detection dogs scampered on to the
scene. United States v. Place marked the Supreme
Courts first foray into this area of the law. 462 U.S. 696,
103 S.Ct. 2637, 77 L.Ed.2d 110 (1983). In Place, two
law enforcement officers grew suspicious that Place might be
carrying narcotics after observing him at Miami International
Airport. Id. at 698, 103 S.Ct. 2637. The officers
remained suspicious after talking with the defendant, though
they ultimately decided not to search his luggage.
Id. The officers looked closely at the luggage tags
on the defendants checked bags and noticed discrepancies
between the two addresses and the phone number the defendant
gave the airline. Id. The officers notified law
enforcement agents in New York of the defendants impending
arrival. Id. Two Drug Enforcement Administration
agents contacted the defendant when he landed, informed the
defendant that they believed he may be transporting illegal
narcotics, and ultimately seized his luggage in order to
subject it to a sniff from a drug-detection dog. Id.
at 698-99, 103 S.Ct. 2637.
Though Place turned on whether the seizure of the
defendants luggage without probable cause violated the
Fourth Amendment, the Court discussed the use of
drug-detection dogs at airports to sniff luggage suspected of
containing illegal narcotics. See id. at
707, 103 S.Ct. 2637. The Court reasoned that exposing
"temporarily detain[ed] personal luggage" to a dog
trained to detect narcotics wasnt a search under the Fourth
Amendment. Id. at 697-98, 103 S.Ct. 2637. The sniff
is "sui generis," stated the Court, because it is
less intrusive than other search techniques and it can only
reveal the "presence or absence of narcotics, a
contraband item." Id. at 707, 103 S.Ct. 2637.
The Courts rationale thus hinged on two notions: (1) A dog
sniff is a minimally intrusive tactic (2) that can only
reveal whether or not contraband is present in the luggage.
Beyond that, the sniff reveals nothing. Despite the narrow
circumstances in which the Court made these statements, they
have formed the foundation for much federal (and state)
jurisprudence on dog sniffs.
The Supreme Court relied on this reasoning in Illinois v.
Caballes to conclude that "the use of a
well-trained narcotics-detection dog— one that does
not expose noncontraband items that otherwise would remain
hidden from public view— during a lawful traffic stop,
generally does not implicate legitimate privacy
interests." 543 U.S. 405, 409, 125 S.Ct. 834, 160
L.Ed.2d 842 (2005) (internal citation omitted) (quoting
Place, 462 U.S. at 707, 103 S.Ct. 2637). In
Caballes, an officer led a drug-detection dog around
a vehicle that was lawfully stopped for speeding.
Id. at 406, 125 S.Ct. 834. The dog alerted at the
trunk, leading to a search that revealed marijuana.
Id. Looking back to Place, the Court
rejected the claim that the dog sniff was unconstitutional
because there was no reasonable suspicion that the defendant
possessed narcotics when he was initially stopped.
Id. at 408-09, 125 S.Ct. 834. Notably, the Court
didnt focus on how the officers in Place had
already grown suspicious that the defendant was engaged in
illegal narcotics activity before stopping and contacting the
defendant. Compare id ., with
Place, 462 U.S. at 698-700, 103 S.Ct. 2637. Instead,
the Court reasoned that reasonable suspicion wasnt necessary
to justify the dog sniff because it could only detect
contraband, and "any interest in possessing contraband
cannot be deemed legitimate, ... thus, governmental conduct
that only reveals the possession of contraband
compromises no legitimate privacy interest. "
Id. at 408, 125 S.Ct. 834 (quoting United States
v. Jacobsen, 466 U.S. 109, 123, 104 S.Ct. 1652, 80
L.Ed.2d 85 (1984)).
C. Colorado Law: Pre-Amendment 64
Our search and seizure jurisprudence took a different path.
In decades past, our opinions demonstrated a willingness to
interpret the state constitution to afford broader
protections than its federal counterpart. Yet, in recent
years, we have moved away from this interpretive
Article II, section 7 of the Colorado Constitution states:
The people shall be secure in their persons, papers, homes
and effects, from unreasonable searches and seizures; and no
warrant to search any place or seize any person or things
shall issue without describing the place to be searched, or
the person or thing to be seized, as near as may be, nor
without probable cause, supported by oath or affirmation
reduced to writing.
In Charnes v. DiGiacomo, this court first charted
its own course in interpreting article II, section 7 to
afford broader protections than the Fourth Amendment. 200
Colo. 94, 612 P.2d 1117 (1980). Charnes concerned a
taxpayers challenge to a subpoena issued to his bank by the
Colorado Department of Revenue seeking the taxpayers
financial records. Id. at 1119. Applying United
States v. Miller, this court concluded that the Fourth
Amendment did not shield the taxpayers financial records
from government seizure because the taxpayer could not claim
any expectation of privacy in the information he shared with
his bank through financial transactions. Id. at 1120
(citing 425 U.S. 435, 96 S.Ct. 1619, 48 L.Ed.2d 71 (1976)).
But, the analysis did not end there. We then looked to
article II, section 7 and concluded that the analytical
framework announced in Katz — whether the
defendant had a subjective expectation of privacy in his bank
records that society was prepared to recognize as
reasonable— was also the framework to be applied under
the Colorado Constitution. See id. at 1120-21.
Noting that Miller "does not determine the
scope of protection provided to individuals in Colorado by
the constitution of this state," we concluded that,
under the Colorado Constitution, bank depositors have a
reasonable expectation of privacy in records concerning their
financial transactions held at banks in Colorado.
Id. Charnes was only the first in a series
of cases holding that article II, section 7 provides greater
privacy protections than the Fourth Amendment. See,
e.g., People v. Sporleder, 666 P.2d 135, 143-44
(Colo. 1983) (rejecting the U.S. Supreme Courts reasoning in
Smith v. Maryland, 442 U.S. 735, 99 S.Ct. 2577, 61
L.Ed.2d 220 (1979), to hold that the installation and use of
a pen register constitutes a search under state law);
People v. Corr, 682 P.2d 20, 27-28 (Colo. 1984)
(applying the reasoning of Sporleder to conclude
that a warrant is required to obtain telephone toll records);
People v. Oates, 698 P.2d 811, 815-16 (Colo. 1985)
(rejecting the reasoning of Karo, 468 U.S. 705, 104
S.Ct. 3296, and holding that the installation and presence of
a tracking device in purchased commercial goods constitutes a
search under the Colorado Constitution).
In People v. Unruh, we considered the constitutional
permissibility of a dog sniff of a locked safe. 713 P.2d 370,
378-79 (Colo. 1986), abrogated by People v.
Esparza, 2012 CO 22, 272 P.3d 367. We concluded that,
despite the less intrusive nature of a dog sniff, it was a
search because the defendant had a reasonable expectation of
privacy in the locked safe. Id. In coming to this
conclusion, we distinguished Place, noting that the
sniff of a persons luggage at an airport was not deemed a
search because the person has "no reasonable expectation
of privacy from an investigative technique as non-intrusive
as a dog sniff" at the airport. Id. at 378. We
then had to decide whether a warrant was necessary to deploy
the drug-detection dog, or whether "something less than
probable cause" could justify the sniff. Id. We
looked to Terry v. Ohio, 392 U.S. 1, 30-31, 88 S.Ct.
1868, 20 L.Ed.2d 889 (1968), where the U.S. Supreme Court
held that an officer may conduct a stop if he has reasonable
suspicion criminal activity is occurring. We analogized
an exploratory dog sniff to the brief investigatory stops at
issue in Terry, and we concluded that the proper
"balance between governmental and individual interests
in this case" necessitated that there be reasonable
suspicion to justify the exploratory sniff. Unruh,
713 P.2d at 379. Our reasoning rested primarily on two
principles: (1) the defendant had a reasonable expectation of
privacy in the item searched (his locked safe), and (2) a dog
sniff, though a search, was a less intrusive search than a
traditional search by hand. Id. at 377-79.
In People v. Haley, we applied the reasoning of
Unruh to conclude that a dog sniff resulting from an
impermissibly prolonged traffic stop violated the protections
of article II, section 7. 41 P.3d 666, 673-74, 676-77 (Colo.
2001), abrogated by Esparza, 2012 CO 22,
272 P.3d 367. This was so because the defendants had "a
privacy interest in their persons and vehicle being free from
unreasonable governmental intrusion, and the drug
investigation following the traffic stop in this case
required reasonable suspicion for the dog sniff search to
proceed." Id. at 674. We acknowledged that
"automobiles enjoy a lesser expectation of privacy in
our society than private homes," but we also noted that
"citizens have a reasonable expectation of privacy from
search and seizure in their cars and in their persons as they
travel the states roads." Id. at 672 (citing
New York v. Class, 475 U.S. 106, 112, 106 S.Ct. 960,
89 L.Ed.2d 81 (1986) ("A citizen does not surrender all
the protections of the Fourth Amendment by entering an
However, in People v. Esparza, we reviewed our prior
precedent on dog sniffs and, in doing so, narrowed its scope.
2012 CO 22, 272 P.3d 367. We concluded that, "[d]espite
our broad language purporting to address dog sniffs in
general," our earlier decisions suggested a "more
limited rule" was appropriate. Id. at ¶ 9, 272
P.3d at 369. Specifically, we noted that our dog-sniff
jurisprudence has "been concerned with the nature of the
particular container being pursued and any official conduct
making it possible for a trained drug dog to sniff the
container in the first place." Id. at ¶ 8, 272
P.3d at 369. Ultimately, we held "that an interest in
possessing contraband cannot be deemed legitimate under the
state constitution any more than under the federal
constitution, and that official conduct failing to compromise
any legitimate interest in privacy cannot be deemed a search
under the state constitution any more than under the federal
constitution." Id. at ¶ 2, 272 P.3d at 368.
Like the U.S. Supreme Court, we based our holding in part on
the purportedly binary nature of the dogs sniff. The sniff,
we reasoned, could only communicate either the presence or
absence of contraband. Id. at ¶ 11, 272 P.3d at 370.
Esparza thus represented a kind of return to the
federal fold. The state of the law was thus: (1) under the
automobile exception, an officer may search a car without a
warrant if that officer has probable cause to believe there
is contraband in the car; (2) an officer doesnt need
reasonable suspicion to walk a drug-detection dog around a
lawfully stopped vehicle because the alert indicates only the
presence of contraband, and people do not have a legitimate
expectation of privacy in contraband; and (3) an alert from a
drug-detection dog could provide probable cause for a
subsequent hand search of the car. See id.
at ¶¶ 10-12, 272 P.3d at 370; see also People v.
Mason, 2013 CO 32, ¶ 10, 310 P.3d 1003, 1005 ("It
is now settled that walking a trained narcotics detection dog
around a car that has not been unlawfully stopped or detained
does not implicate the protections of either the Fourth
Amendment or Article II, section 7 of the state
constitution."). And so it has been for the better part
of a decade.
D. Colorado Law: Post-Amendment 64
Has the passage of Amendment 64 altered this settled terrain?
We began to explore this question in our recent decisions in
People v. Zuniga, 2016 CO 52, 372 P.3d 1052, and
People v. Cox, 2017 CO 8, 401 P.3d 509. In both
Zuniga and Cox, we found probable cause
supporting an automobile search based on a confluence of
factors, including the positive alert of a drug-detection dog
that was trained to alert to marijuana. Yet, in
Zuniga, we concluded that the alert was
legally ambiguous because a drug-detection dog cant
distinguish legal marijuana from illegal marijuana, or legal
marijuana from illegal narcotics. See ¶¶ 18-23, 372
P.3d at 1057-59. Despite this ambiguity, we held that the
alert was still relevant to the overall probable cause
analysis. Id. Likewise in Cox, we concluded
that the positive alert of a drug-detection dog was one
factor, among many, supporting a finding of probable cause to
search a stopped vehicle.¶ 17, 401 P.3d at 512-13.
In both Zuniga and Cox, we declined to
address (1) whether the sniff of a dog trained to detect
marijuana was a search, and (2) whether a positive alert from
a dog trained to detect marijuana alone could establish
probable cause. Significantly however, these two recent
decisions suggest the answer to the latter question is no. We
acknowledged that, with the legalization of small amounts of
marijuana, a dogs alert doesnt provide a yes-or-no answer
to the question of whether illegal narcotics are present in a
vehicle. At most, the alert could be "suggestive of
criminality," but not determinative on its own.
See Zuniga, ¶ 23, 372 P.3d at 1059. Had the
alert alone sufficed, there would have been no need to
evaluate other circumstances in either Zuniga or
Cox . Yet, we did just that. Thus, in finding that
an alert from a drug-detection dog trained to find marijuana
is ambiguous, Zuniga and Cox represent a
tentative step away from the federal approach. See,
e.g., Harris, 568 U.S. at 240, 247-48, 133
S.Ct. 1050 (concluding that an alert from a well-trained,
reliable drug-detection dog could supply probable cause to
search a vehicle).
To be sure, marijuana remains illegal under federal law. The
Federal Controlled Substances Act prohibits the possession of
marijuana for nearly all uses. 21 U.S.C. § 812(c)(10) (2012);
21 U.S.C. § 812(b)(1)(A)-(C) (2012); 21 U.S.C. § 844(a)
(2012). "There is no exception for marijuana use for
medical purposes, nor is there an exception for use in
compliance with state law." People v. Crouse,
2017 CO 5, ¶ 11, 388 P.3d 39, 42 (citing Gonzales v.
Raich, 545 U.S. 1, 14, 125 S.Ct. 2195, 162 L.Ed.2d 1
(2005)). Consequently, marijuana remains contraband under
federal law and, arguably, Kilos sniff was not a search
under the U.S. Supreme Courts interpretation of the Fourth
Amendment in Caballes . See McKnight, ¶
18 n.4. This, however, leaves unanswered the question of
whether Kilos sniff was nonetheless a search under the
corresponding provisions of our state
We have opined that, despite the substantial similarity
between article II, section 7 and the Fourth Amendment,
"we are not bound by the United States Supreme Courts
interpretation of the Fourth Amendment when determining the
scope of state constitutional protections."
Sporleder, 666 P.2d at 140. "There is no reason
to think, as an interpretive matter, that constitutional
guarantees of independent sovereigns, even guarantees with
the same or similar words, must be construed in the same