IN THE SUPREME COURT OF THE STATE OF KANSAS
No. 113,888
STATE OF KANSAS,
Appellee,
v.
LAWRENCE C. HUBBARD,
Appellant.

SYLLABUS BY THE COURT
1.
On a motion to suppress evidence, an appellate court reviews the factual findings
underlying the trial court's suppression decision using a substantial competent evidence
standard and the legal conclusion drawn from those factual findings using a de novo
standard. The court does not reweigh evidence.

2.
Warrantless searches are considered unreasonable and invalid unless they fall
within a recognized exception to the warrant requirement. It is the State's burden to
demonstrate a challenged search was lawful.

3.
A warrantless search is permissible when there is probable cause for the search
and exigent circumstances justifying an immediate search.

1

 4.
Probable cause to support a search can be established if the totality of the
circumstances indicates there is a fair probability the place to be searched contains
contraband or evidence of a crime.

5.
The totality of the circumstances surrounding a law enforcement officer's detection
of the smell of raw marijuana emanating from a residence can supply probable cause to
believe the residence contains contraband or evidence of a crime. Such circumstances
include, but are not limited to, proximity to the odor's source, reported strength of the
odor, experience identifying the odor, elimination of other possible sources of the odor,
and the number of witnesses testifying to the odor's presence. This is a case-by-case
determination based on the circumstances. Not all cases relying on odor will have the
same result.

6.
Exigent circumstances include situations when a law enforcement officer
reasonably believes there is a threat of imminent loss, destruction, removal, or
concealment of evidence or contraband.

7.
When determining the existence of an exigency based on the potential loss of
evidence, a reviewing court should consider various circumstances, including: (a) the
time needed to secure a search warrant; (b) the reasonableness of the officers' belief the
evidence may be immediately lost; (c) potential danger to the officers guarding the site
while awaiting a warrant; (d) whether those persons with possession of the evidence are
aware of the officers' presence; and (e) the ease with which the evidence might be
destroyed or hidden.
2

 8.
Whether a witness—expert or layperson—is qualified to testify as to an opinion is
to be determined by the trial court in the exercise of its discretion.

Review of the judgment of the Court of Appeals in an unpublished opinion filed April 22, 2016.
Appeal from Douglas District Court; PEGGY C. KITTEL, judge. Opinion filed December 7, 2018.
Judgment of the Court of Appeals affirming the district court is affirmed. Judgment of the district court is
affirmed.

James E. Rumsey, of Lawrence, argued the cause and was on the briefs for appellant.

Kate Duncan Butler, assistant district attorney, argued the cause, and Patrick J. Hurley, assistant
district attorney, Charles E. Branson, district attorney, and Derek Schmidt, attorney general, were on the
brief for appellee.

The opinion of the court was delivered by

BILES, J.: Lawrence C. Hubbard appeals his misdemeanor convictions of
possession of marijuana and possession of drug paraphernalia. He claims the drug
evidence should have been suppressed because: (1) the initial warrantless entry into his
apartment for a security sweep was premised on a police officer's statement that she
smelled raw marijuana while standing at the front door; (2) an affidavit supporting a
search warrant omitted material facts; and (3) the officer's suppression-hearing testimony
about smelling the raw marijuana odor was inadmissible expert testimony. A Court of
Appeals panel affirmed. State v. Hubbard, No. 113,888, 2016 WL 1614177 (Kan. App.
2016) (unpublished opinion). We find no error and affirm.

3

 FACTUAL AND PROCEDURAL BACKGROUND
While on routine surveillance at a local convenience store, Lawrence Police
Officer Kimberly Nicholson checked a vehicle's license plate. That records check
indicated the car had been stopped several weeks earlier with Irone Revely driving. It was
noted there was an active arrest warrant for Revely's brother, Chayln Revely. Nicholson
confirmed Irone was the driver, and she believed the passenger matched Chayln's
description.

Nicholson followed the vehicle, looking for a traffic violation that would permit a
vehicle stop and might allow the officer to confirm the passenger's identity. No violation
occurred, so Nicholson followed the vehicle to an apartment complex. The passenger got
out and ran into an apartment. Irone trailed behind. Nicholson approached and asked
Irone if the person who ran into the apartment was his brother. Irone did not answer and
continued walking toward the apartment with Nicholson following.

The apartment sweep and search
As it turned out, Hubbard was the passenger Nicholson saw. He came out of the
apartment to talk to the officer and acknowledged he lived there.

Nicholson later testified she was about 2 feet from the front door when Hubbard
exited. She further testified she "smelled a strong odor of raw marijuana emanating from
the apartment." The officer questioned Irone and Hubbard about the smell. Hubbard
denied smelling anything and said his lawyer told him humans cannot detect a marijuana
odor.

4

 The front window blinds to the apartment were raised about a foot above the sill,
allowing Nicholson to see inside. The officer saw five to seven people in the apartment.
She testified she could only look for a few seconds before Hubbard went back inside and
shut the blinds. As Hubbard reentered, Nicholson again smelled raw marijuana. Around
this time, additional police officers arrived.

The officers decided to apply for a warrant to search the apartment. They ordered
everyone to leave. No one was searched as they left. The officers testified they did not
smell marijuana on anyone as they were leaving.

Three officers, including Nicholson, did a security sweep to make sure no one
remained in the apartment. Nicholson testified the sweep was to ensure no one could
destroy evidence or pose a threat to the officers. She testified the sweep was limited to
places where a person could hide. The officers observed drug paraphernalia, a handgun,
and a locked safe in a closet in Hubbard's room.

Nicholson applied for the search warrant, which was granted. During the warrant's
execution, officers pried open the safe and found 25.07 grams of raw marijuana inside a
Tupperware container. The officers also found a small amount of marijuana on a partially
burnt cigarillo in the living room and several bongs, which were clean and had no
marijuana residue. The State charged Hubbard with one count of possession of marijuana
and one count of possession of drug paraphernalia, both class A nonperson
misdemeanors.

The suppression motion
Hubbard filed a motion to suppress the evidence from the apartment. He argued
the officers' initial sweep was an illegal search that invalidated the subsequent warrant.
5

 He argued the smell of marijuana detected by an officer does not by itself provide the
probable cause for a search. He also contended Nicholson lied about smelling raw
marijuana or possibly spoke with reckless disregard for the truth. Finally, Hubbard
claimed there was no factual basis for the protective sweep prior to obtaining the search
warrant.

At a hearing on the suppression motion, Nicholson and Lawrence Police Officer
Ronald Ivener testified. Both described noticing the strong marijuana smell. Nicholson
said she "smelled a strong odor of raw marijuana emanating from the apartment." Ivener
testified that when the door opened and closed, he could identify "the potent smell of raw
marijuana emitting from inside the apartment." He also said he smelled a "mixture of
both" raw and burnt marijuana during the sweep.

Hubbard contradicted the officers in his testimony. He said he did not run into his
apartment, but merely "power-walked" because he was having a party and wanted
everyone to quiet down since a police car was in the parking lot. He claimed there was no
marijuana smell, only cigarette smoke and incense. Hubbard denied Nicholson was 2 feet
from the front door when she claimed to smell raw marijuana, insisting she was 6 or 7
feet away. He contended Nicholson fabricated smelling marijuana after he became angry
with her because he believed the officer racially profiled him by assuming he was Irone's
brother with the active arrest warrant.

The suppression hearing transcript reflects the State offered Nicholson's probable
cause affidavit into evidence and that the district court admitted it. But Hubbard did not
include that affidavit in the record on appeal.

Nicholson testified officers found raw marijuana in a safe in Hubbard's bedroom
closet and burnt marijuana in the living room while executing the warrant. She also said
6

 the officers observed items of "evidentiary value," including "bongs and pipes sitting on
the window sill" of Hubbard's bedroom, during the initial sweep.

The district court denied the motion to suppress. Among its factual findings, the
court concluded: (1) Nicholson had "detected the smell of raw marijuana 200 to 500
times and burnt marijuana 100 to 300 times" in her law enforcement training and
professional experience; (2) when Hubbard came out of his apartment, closing the door
behind him, both Nicholson and Ivener could smell what they identified as the odor of
raw marijuana coming from the apartment; (3) Ivener testified the smell was "potent" and
"overwhelming"; (4) Nicholson observed two bongs and six smoking pipes on a
windowsill and found a gun under a bed and another bong and a safe in the closet all
located in the back bedroom while conducting the security sweep; (5) Nicholson smelled
raw marijuana during the sweep; and (6) a search warrant was requested by Nicholson,
supported by affidavit, setting forth the evening's events, including the security sweep.

The court said it gave "no weight" to an academic study introduced by Hubbard to
support his argument that the officers could not accurately identify the marijuana smell.
The 2004 article from the Smell and Taste Center, University of Pennsylvania School of
Medicine, is entitled: "Marijuana Odor Perception: Studies Modeled from Probable
Cause Cases." Hubbard argued it cast serious doubt about whether humans can accurately
identify marijuana based on smell, but the court discredited the study's value. The court
determined the study's research parameters did not accurately compare to the facts in
Hubbard's case. The court noted the article limited its findings to suggest there is "no
convincing evidence that lay persons could reliably detect the marijuana odor under the
test conditions." But, the court observed, the article's authors admitted training could
improve detection performance.

7

 The district court relied on State v. MacDonald, 253 Kan. 320, 856 P.2d 116
(1993), and State v. Riley, No. 93,127, 2006 WL 90089 (Kan. App. 2006) (unpublished
opinion), in concluding the odor of marijuana coming from the apartment supplied
probable cause "to seek and obtain a search warrant." The court also noted Nicholson
included observations in the warrant affidavit about drug paraphernalia during the
protective sweep, when stating: "The strong odor of raw marijuana coming from the
residence, along with the observation of drug paraphernalia in the apartment gave
probable cause to the officers to obtain a search warrant."

Hubbard moved for reconsideration. He argued when the officers testified about
smelling marijuana, they were experts under K.S.A. 2017 Supp. 60-456, so their
testimony would only be admissible after demonstrating the reliability of their methods—
or, in this case, their ability to identify marijuana by smell. The court denied
reconsideration and ruled Nicholson testified as a lay person. The court reasoned:

"She's not an expert in the field of odors. She's not an expert in marijuana, but she does
have training. And there are numerous cases that allow for officers to testify based on
their individual personal observations and their training just to become a police officer,
and she's testified to that, and this court is aware of that training. I find her training was
sufficient. It goes more to the weight that her testimony gives and not the admissibility of
it."

After a bench trial, the court adopted its factual findings set out in its initial ruling
on the suppression motion and made additional findings that both Nicholson and Ivener
identified the marijuana odor, that the officers discovered drug paraphernalia while
conducting a sweep prior to obtaining the search warrant, and that the drug paraphernalia
was consistent with personal drug use. Relying on these findings the court convicted
Hubbard on both counts.
8

 The court sentenced Hubbard to two 12-month jail sentences and granted
probation. Hubbard appealed.

The Court of Appeals decision
On appeal, Hubbard argued the suppression motion should have been granted
because the officers' warrantless entry into his residence, ostensibly for officer safety and
to prevent evidence destruction, violated the Fourth and Fourteenth Amendments to the
United States Constitution and § 18 of the Kansas Constitution Bill of Rights. The panel
declined to consider the § 18 claim because Hubbard only mentioned it once and did not
explain its relevance. It also noted § 15 prohibits unreasonable searches and seizures, not
§ 18. Hubbard, 2016 WL 1614177, at *4.

The State argued probable cause existed for the search warrant based on the
officers detecting the raw marijuana odor originating from Hubbard's apartment, even if
the protective sweep was not reasonable. Moreover, the sweep was reasonable under the
probable cause plus exigent circumstances exception to the warrant requirement, the State
contended, because officer safety and the possibility for evidence destruction were
exigent circumstances justifying warrantless entry. It also argued even if the officers
lacked probable cause for the warrant, the evidence seized from Hubbard's bedroom
remained admissible under the good-faith exception since the officers applied for a
warrant before attempting the search. 2016 WL 1614177, at *4.

The panel held the officer safety justification was inapplicable because it is limited
to warrantless sweeps incident to a lawful arrest, noting the sweep here occurred prior to
Hubbard's arrest. The panel also held the officers failed to articulate specific facts that
reasonably warranted a belief that anyone in Hubbard's apartment posed a danger to the
officers or others. 2016 WL 1614177, at *5.
9

 But the panel agreed with the State that the sweep was justified by the officers'
perceived need to preserve evidence. It noted this need can only supply exigent
circumstances justifying a warrantless search if there is probable cause to believe a crime
has been committed and that evidence may be found in a specific place. 2016 WL
1614177, at *5 (citing State v. Ibarra, 282 Kan. 530, 544, 147 P.3d 842 [2006]). And the
panel held the smell of marijuana provided probable cause to believe "the crime of
possession of marijuana had been committed and that evidence of that crime might be
found in Hubbard's apartment." 2016 WL 1614177, at *5-7 (comparing State v.
MacDonald, 253 Kan. 320, 856 P.2d 116 [1993], with Ibarra, 282 Kan. 530, and State v.
Riley, No. 93,127, 2006 WL 90089 [Kan. App. 2006] [unpublished opinion]).

While acknowledging this court had not yet addressed whether marijuana odor
alone is sufficient to find probable cause to justify the warrantless search of a residence,
the panel concluded probable cause based upon the strong odor of marijuana detected by
the two officers justified the warrantless entry "at least for the limited purpose of
preventing the destruction of evidence until a search warrant could be obtained." 2016
WL 1614177, at *7.

In so deciding, it distinguished State v. Huff, 278 Kan. 214, 92 P.3d 604 (2004),
from Hubbard's case. 2016 WL 1614177, at *7. Unlike Huff, the panel noted, in which
"the officers heard no noise to indicate that there were other occupants," Nicholson and
Ivener knew other people were inside the apartment. Hubbard, 2016 WL 1614177, at *7.
Additionally, the panel viewed Huff as not particularly helpful to Hubbard's case because
Huff addressed "whether there were exigent circumstances to justify a search or entry into
a private residence to effectuate a warrantless arrest." 2016 WL 1614177, at *8.

10

 Instead, the panel looked to State v. Fewell, 286 Kan. 370, 384-85, 184 P.3d 903
(2008), and noted exigent circumstances involving the threat of destruction of evidence
exist when ""'the police officer reasonably believes there is a threat of imminent loss,
destruction, removal, or concealment of evidence or contraband. In each case, the
particular facts must be considered."'" 2016 WL 1614177, at *9. The panel then quoted
the factors articulated in State v. Dugan, 47 Kan. App. 2d 582, 276 P.3d 819 (2012),
which was also an evidence-protection case:
"'(1) the time needed to secure a search warrant; (2) the reasonableness of the officers'
belief the evidence may be immediately lost; (3) potential danger to the officers guarding
the site while awaiting a warrant; (4) whether those persons with possession of the
evidence are aware of the officers' presence; and (5) the ease with which the evidence
might be destroyed or hidden. [Citations omitted.]'" 2016 WL 1614177, at *9.

Next, the panel discarded Hubbard's argument that material omissions in the
affidavit invalidated the warrant because Hubbard failed to include that affidavit in the
record on appeal. 2016 WL 1614177, at *11.

Finally, the panel addressed Hubbard's contention that Nicholson's testimony
should be deemed expert testimony and ruled inadmissible because it was not sufficiently
reliable. The panel concluded Nicholson's testimony was governed by K.S.A. 60-419:

"Under that statute, a witness may testify on a relevant or material matter as long as there
is evidence that he or she 'has personal knowledge thereof, or experience, training or
education if such be required. Such evidence may be by the testimony of the witness
himself or herself.' Nicholson's testimony that she smelled raw marijuana was based on
her personal knowledge of the odor of raw marijuana, and she testified at the suppression
hearing about the training and experience that allowed her to recognize the odor of raw
marijuana. Thus, the district court did not err in admitting the testimony." 2016 WL
1614177, at *12.

11

 The panel affirmed the district court's decisions but said it "stopp[ed] short of
finding that the odor of marijuana would have provided probable cause for the officers to
conduct a detailed search of Hubbard's apartment for illicit drugs, including drawers and
containers within the apartment" because that detailed search occurred after the warrant's
issuance. 2016 WL 1614177, at *7.

This court granted Hubbard's petition for review. Jurisdiction is proper. See K.S.A.
20-3018(b) (providing for petitions for review of Court of Appeals decisions); K.S.A. 602101(b) (Supreme Court has jurisdiction to review Court of Appeals decisions upon
petition for review). We address the issues subject to our review in the order the panel
considered them.

We further note Hubbard's attempt to resurrect on review his state constitutional
claim by now referencing § 15 of the Kansas Constitution, rather than § 18. But he did
not seek review of the panel's rejection of that issue, so we ignore this question as the
panel did. See State v. Johnson, 297 Kan. 210, 226-28, 301 P.3d 287 (2013) (declining to
address issue not raised or fairly included in petition because whether review would have
been granted on issue was speculative and the State was deprived of opportunity to
challenge propriety of reviewing it).

MOTION TO SUPPRESS
The State did not seek review of the panel's holding that officer safety did not
justify the initial sweep of Hubbard's apartment, so that much is resolved. See State v.
McBride, 307 Kan. 60, 62, 405 P.3d 1196 (2017). Our focus is on Hubbard's challenge to
the panel's ruling that the potential loss of evidence exception permitted officers to empty
the apartment and sweep the premises looking for stragglers.
12

 Hubbard argues the officers' claims of smelling marijuana at the front door did not
properly support the search. Or, as he states the controversy to us: "No Kansas Supreme
Court case has held that odor alone of marijuana can provide probable cause to search a
residence." This court previously has recognized the law in Kansas is unsettled whether
the smell of marijuana alone supplies probable cause to search a residence. Huff, 278
Kan. at 222.

Standard of review
Faced with a motion to suppress evidence, the State bears the burden of proving
the search and seizure were lawful. K.S.A. 22-3216(2); see also State v. Gray, 306 Kan.
1287, 1302, 403 P.3d 1220 (2017). As to the trial court's suppression order,

"'an appellate court reviews the factual underpinnings of the decision under a substantial
competent evidence standard. The ultimate legal conclusion drawn from those facts is
reviewed de novo. . . . Substantial evidence refers to evidence that a reasonable person
could accept as being adequate to support a conclusion. . . . This court does not reweigh
the evidence, assess the credibility of the witnesses, or resolve evidentiary conflicts.
[Citations omitted.]' State v. Mattox, 305 Kan. 1015, 1035, 390 P.3d 514 (2017)." State v.
Brown, 306 Kan. 1145, 1151, 401 P.3d 611 (2017).

Discussion
We begin our consideration mindful of the facts as determined by the district court
after an evidentiary hearing. Two officers testified they smelled marijuana. Nicholson
estimated she was about 2 feet from the apartment door, which was opened and closed
twice in her presence. Ivener testified the marijuana smell was "strong" and "potent." The
district court found both officers credible and experienced at identifying the smell of
marijuana. It specifically noted Nicholson "detected the smell of raw marijuana 200 to
13

 500 times and burnt marijuana 100 to 300 times." Substantial competent evidence
supports these factual findings. And to the extent Hubbard challenged the officers'
credibility, those determinations are not subject to our review. See State v. Schoonover,
281 Kan. 453, 517, 133 P.3d 48 (2006) (holding trial court's decision to credit
magistrate's testimony that prior contact with defendant did not affect issuance of warrant
was not subject to challenge on appeal from adverse ruling on suppression motion).

The ultimate question is whether Hubbard was entitled to have the evidence
obtained during the search warrant execution suppressed because of what he believes was
the officers' unlawful, warrantless entry into his home. In the district court, Hubbard
sought suppression of the evidence seized pursuant to the search warrant, noting the
officers located "many of the items seized" during the initial warrantless entry. In
answering this question, we do not reach whether the search warrant itself was valid
because the record on appeal is incomplete for that purpose. Rather, we agree with the
lower courts that the facts as found by the district court established probable cause to
believe contraband would be found inside the apartment. We further hold an exigent
circumstance—the need to prevent evidence destruction—supplied an exception to the
warrant requirement that permitted the officers to search the apartment for individuals
who might have been remaining within it. And because the sweep was lawful, it cannot
supply a basis for challenging the warrant.

The Fourth Amendment to the United States Constitution guarantees: "The right
of the people to be secure in their persons, houses, papers, and effects, against
unreasonable searches and seizures . . . ." And the judicially created exclusionary rule
prevents evidence obtained through an illegal search or seizure from being admitted at
trial. Mapp v. Ohio, 367 U.S. 643, 655, 81 S. Ct. 1684, 6 L. Ed. 2d 1081 (1961). This
exclusionary rule "safeguards Fourth Amendment rights by preventing the use of
unconstitutionally obtained evidence in criminal proceedings against victims of illegal
14

 searches." State v. Pettay, 299 Kan. 763, 768, 326 P.3d 1039 (2014). For the exclusionary
rule to apply, there first must be a constitutional violation.

When the affidavit supporting a search warrant is challenged, a reviewing court
assesses whether that affidavit supplied the issuing judge with a substantial basis for
finding probable cause. State v. Fisher, 283 Kan. 272, 300, 154 P.3d 455 (2007). And
when the affidavit contains both lawfully and unlawfully obtained information, the court
asks whether the affidavit supplied a substantial basis for finding probable cause absent
the unlawfully obtained information. 283 Kan. at 303-04. We have previously described
this as "probable cause at least once removed," i.e., "deference is built into . . . the
'substantial basis' standard." State v. Hicks, 282 Kan. 599, 613, 147 P.3d 1076 (2006). If a
substantial basis existed for finding probable cause, the warrant was valid and evidence
obtained pursuant to it will not be suppressed. See Fisher, 283 Kan. at 309. But see State
v. Epperson, 237 Kan. 707, 718-19, 703 P.2d 761 (1985) (evidence discovered as result
of Fourth Amendment violation subject to exclusion as fruit of the poisonous tree).

In addition, when law enforcement reasonably relies on a search warrant later
found to lack probable cause, the exclusionary rule does not bar the evidence's use unless
one of four exceptions applies:

"(1) the magistrate issuing the warrant was deliberately misled by false information; (2)
the magistrate wholly abandoned his or her detached or neutral role; (3) there was so little
indicia of probable cause contained in the affidavit that it was entirely unreasonable for
the officers to believe the warrant was valid; or (4) the warrant so lacked specificity that
officers could not determine the place to be searched or the items to be seized." State v.
Hoeck, 284 Kan. 441, 464, 163 P.3d 252 (2007).

For warrantless searches, the principles are different. The Fourth Amendment
prohibits unreasonable searches and seizures, and warrantless searches are per se
15

 unreasonable unless they fall within an exception to the warrant requirement. State v.
Neighbors, 299 Kan. 234, 239, 328 P.3d 1081 (2014) ("[A] warrantless entry into a
private dwelling by law enforcement officers is considered unreasonable and invalid
unless it falls within a recognized exception to the warrant requirement."). One such
exception—the one with which we are presently concerned—is when officers possess
both probable cause for a search and exigent circumstances justifying that it be carried
out immediately. See State v. Ibarra, 282 Kan. 530, 536, 147 P.3d 842 (2006).

The principles applicable to warrantless searches might be relevant to determining
a search warrant's validity because, if information obtained through a warrantless search
is included in an affidavit, whether that information was lawfully or unlawfully obtained
affects the analysis concerning the warrant's validity. And because this case involves both
a warrant and a warrantless search, the inevitable discovery doctrine—an exception to the
exclusionary rule under which "the prosecution may use evidence it obtained illegally but
would have obtained legally in any event"—is also relevant to fully resolve the Fourth
Amendment issues this fact pattern raises. State v. Ackward, 281 Kan. 2, 18, 128 P.3d
382 (2006).

Within this context, if the warrant was valid, the exclusionary rule cannot apply in
Hubbard's case because the warrant resulted in the marijuana being discovered and the
paraphernalia's discovery was inevitable. But even if the warrantless sweep was unlawful,
the warrant might still have been valid if the affidavit provided a substantial basis to find
probable cause—even after excluding information learned during the warrantless sweep.
Further, even if the warrant was invalid, exclusion might not be required if law
enforcement reasonably relied on it, unless one of the four good-faith exceptions applies.

Unfortunately, our ability to fully answer this array of suppression questions is
stymied by Hubbard's failure to include the search warrant affidavit in the appellate
16

 record. See State v. McCullough, 293 Kan. 970, 999, 270 P.3d 1142 (2012) ("The party
claiming an error occurred has the burden of designating a record that affirmatively
shows prejudicial error."). The panel observed this problem as well. Hubbard, 2016 WL
1614177, at *11.

We are uncertain what information was provided in the affidavit, though the
record indicates it contained at least Nicholson's belief she smelled raw marijuana and
likely her observations about drug paraphernalia during the protective sweep. So even
assuming some information was unlawfully obtained, without inspecting the remaining
circumstances detailed in the affidavit it is impossible for us to rule the district court
erred by refusing to suppress the evidence due to a defect in the search warrant affidavit.

But we need not dwell further on this procedural default because we agree with the
panel that the probable cause plus exigent circumstances exception permitted the
warrantless sweep. Therefore, to the extent the paraphernalia evidence and the search
warrant were fruits of a warrantless search, the sweep was not illegal and the challenged
evidence is not subject to exclusion.

Marijuana odor supplied probable cause
This court has provided the following definition for probable cause:

"'Probable cause is the reasonable belief that a specific crime has been committed and
that the defendant committed the crime. Probable cause exists where the facts and
circumstances within the arresting officers' knowledge and of which they had reasonably
trustworthy information are sufficient in themselves to warrant a man of reasonable
caution in the belief that an offense has been or is being committed.

17

 "'When determining whether probable cause exists, an appellate court considers
the totality of the circumstances, including all of the information in the officer's
possession, fair inferences therefrom, and any other relevant facts, even if they may not
be admissible on the issue of guilt.'" State v. Ramirez, 278 Kan. 402, 406, 100 P.3d 94
(2004) (quoting State v. Abbott, 277 Kan. 161, Syl. ¶¶ 2-3, 83 P.3d 794 [2004]).

Cast more pointedly in terms of probable cause for a search, probable cause "can
be established if the totality of the circumstances indicates there is a fair probability that
the place to be searched contains contraband or evidence of a crime." State v. SanchezLoredo, 294 Kan. 50, Syl. ¶ 2, 272 P.3d 34 (2012) (warrantless vehicle search); see also
Hicks, 282 Kan. at 603 (noting magistrate judge considering whether to issue search
warrant charged with making "'"a practical, common-sense decision whether, given all
the circumstances set forth in the affidavit . . . , including the 'veracity' and 'basis of
knowledge' of [any] persons supplying hearsay information, there is a fair probability that
contraband or evidence of a crime will be found in a particular place"'") (quoting State v.
Gilbert, 256 Kan. 419, 421, 886 P.2d 365 [1994]).

In State v. MacDonald, 253 Kan. 320, 856 P.2d 116 (1993), the court held that the
odor of marijuana detected by an officer trained and experienced in identifying the smell
provided probable cause to search a vehicle. 235 Kan. at 325. The officer observed the
smell during a checklane stop when the driver's window was open. The MacDonald court
held the officer had probable cause to search the car, by noting that "[a] majority of
courts have found that marijuana odor detected by an experienced law enforcement
officer can provide sufficient probable cause to support a warrantless search." 253 Kan. at
325. Similarly, Nicholson and Ivener smelled what they identified as the odor of raw
marijuana coming from the apartment when Hubbard twice opened the front door in their
presence.

18

 Hubbard's arguments on appeal suggest the rule from MacDonald should not
apply when the place to be searched is a residence and that the odor of marijuana cannot
supply a basis for probable cause in that context. He bases this latter contention on the
journal article he provided to the district court. We disagree with Hubbard. The officer's
ability to discern the smell of marijuana was an issue of fact appropriately resolved by the
district court against Hubbard based on the evidence from the suppression hearing.

The United States Supreme Court has addressed the relationship between odors
and probable cause. In Taylor v. United States, 286 U.S. 1, 52 S. Ct. 466, 76 L. Ed. 951
(1932), law enforcement agents during Prohibition smelled whiskey coming from a
garage while conducting a late-night investigation into complaints about the structure.
They looked through a small opening and saw many cardboard cases, which they
presumed contained illegal contraband. They searched the garage without a warrant and
found illegal alcohol. The Court reversed the defendant's conviction primarily because
the officers failed to obtain a search warrant despite ample opportunity to do so. 286 U.S.
at 6. But in so holding, the Court stated "[p]rohibition officers may rely on a distinctive
odor as a physical fact indicative of possible crime; but its presence alone does not strip
the owner of a building of constitutional guaranties (Const. Amend. 4) against
unreasonable search." (Emphasis added.) 286 U.S. at 6.

Sixteen years later, the Court decided Johnson v. United States, 333 U.S. 10, 68 S.
Ct. 367, 92 L. Ed. 436 (1948), in which experienced narcotics officers searched a hotel
room after recognizing the "distinctive and unmistakable" smell of opium. 333 U.S. at 12.
The defendant relied on Taylor for the proposition that odors cannot be evidence
sufficient to constitute probable grounds for any search. But the Court rejected this and
clarified that Taylor merely held

19

 "odors alone do not authorize a search without warrant. If the presence of odors is
testified to before a magistrate and he finds the affiant qualified to know the odor, and it
is one sufficiently distinctive to identify a forbidden substance, this Court has never held
such a basis insufficient to justify issuance of a search warrant. Indeed it might very well
be found to be evidence of most persuasive character." 333 U.S. at 13.

The Johnson Court explained that evidence may support a neutral magistrate in
granting a search warrant, but allowing warrantless searches based on the same evidence
"would reduce the [Fourth] Amendment to a nullity and leave the people's homes secure
only in the discretion of police officers." 333 U.S. at 14. The Court noted, though, that
"exceptional circumstances" may justify dispensing with the warrant requirement,
including a suspect's flight likelihood; mobility of the area to be searched, e.g., a vehicle;
and the threat of removal or destruction of evidence. 333 U.S. at 14-15.

Both Taylor and Johnson support the general proposition that sufficiently
distinctive odors that betray illegal activity to those who would know the odor are enough
to find probable cause for issuing a warrant. And Johnson suggests that when probable
cause exists, an exigent circumstance such as removal or destruction of evidence may
permit officers to bypass the warrant requirement entirely—justifying a warrantless
search.

Other jurisdictions have weighed in on this and provide authority that the distinct
smell of marijuana supplies probable cause under appropriate circumstances. See United
States v. Sifuentes, 504 F.2d 845, 848 (4th Cir. 1974) (equating smelling marijuana with
the plain view doctrine, stating "[t]hese facts [—seeing the boxes and smelling
marijuana—] combined to place the contraband in plain view, that is, obvious to the
senses"); Mendez v. People, 986 P.2d 275, 280-81 (Colo. 1999) ("In holding that
probable cause existed in this case, we emphasize that the smell of burning marijuana is
20

 sufficiently distinctive as to be readily identifiable to a trained police officer."); People v.
Baker, 813 P.2d 331, 333 (Colo. 1991) ("[O]fficers had probable cause to believe a crime
was being committed when they smelled burned marijuana."); State v. Hughes, 233 Wis.
2d 280, 291-92, 607 N.W.2d 621 (2000) ("When the strong smell of marijuana is in the
air, there is a 'fair probability' that marijuana is present. This is common sense."); United
States v. Newton, 463 Fed. Appx. 462, 466-67 (5th Cir. 2012) (unpublished opinion)
(holding probable cause to obtain a search warrant sufficient based on the smell of
marijuana coming from an apartment and the resident fleeing from the officers when he
knocked on the door); see also United States v. DeLeon, 979 F.2d 761, 764-65 (9th Cir.
1992) (smell of growing marijuana alone did not provide probable cause because "there
was no finding that [the person claiming to smell marijuana] was qualified to recognize
the odor of growing marijuana, which doubtlessly differs from the odor of cured or
burning marijuana").

In academic writings, LaFave notes:

"The Supreme Court was not off the mark in Johnson in saying that an odor may
be 'evidence of the most persuasive character.' As the illegal substance cases illustrate,
the sense of smell will often make more certain a finding of probable cause than the sense
of sight. This, of course, is because there are some truly distinctive odors, while many
objects commonly associated with the possession and use of illegal substances (e.g., a
green plant, a grassy substance, a handrolled cigarette, pills, a pipe, a folded dollar bill, a
plastic baggie, or a glassine envelope) may in fact be innocent." 2 LaFave, Search &
Seizure § 3.6(b) (5th ed. 2012).

See also Sprow, Wake Up and Smell the Contraband: Why Courts That Do Not Find
Probable Cause Based on Odor Alone Are Wrong, 42 Wm. & Mary L. Rev. 289 (2000).

21

 Hubbard largely relies on Huff, in which the court assumed a skeptical view about
the import of marijuana odor in determining probable cause. 278 Kan. at 221-22. The
court rejected an argument that the facts constituted exigent circumstances to justify a
warrantless apartment entry, as well as an alternative argument that the evidence should
have been admitted under the inevitable discovery doctrine even without the probablecause-plus-exigent-circumstances exception. Huff, 278 Kan. at 220-21. In that case, when
officers responded to a citizen complaint about noise and a marijuana odor coming from
the apartment, they smelled burnt marijuana when the resident exited to speak with them.
The officers entered the apartment over the resident's objection and found defendant
inside, along with another person who was holding a marijuana pipe and had
methamphetamine in his pocket. The officers then obtained a search warrant, through
which they discovered syringes, methamphetamine, and a slip of paper bearing
defendant's name.

In dismissing the exigent circumstances argument, the Huff court reasoned that
"[p]robable cause was weak, if it existed at all" and held there were no exigent
circumstances because "[o]nce [the resident] came outside, the officers had no evidence
that even one other person remained in the apartment" and "[t]he absence of evidence that
someone remained inside also meant the officers had no reason to worry about evidence
destruction." 278 Kan. at 221. The Huff court stated "few jurisdictions have held that the
smell of marijuana emanating from a private residence alone is sufficient to establish
probable cause to support a search warrant. [Citations omitted.] Generally something
more than 'plain smell' is required." 278 Kan. at 221. The court cited as support United
States v. Padron, 657 F. Supp. 840 (D. Del. 1987), which involved a vehicle search, as
did the cases Padron cited as its support.

The Hubbard panel noted this distinction but found MacDonald persuasive
nonetheless in context with other cases and the officers' testimony. Hubbard, 2016 WL
22

 1614177, at *6-7. The panel cited State v. Riley, No. 93,127, 2006 WL 90089 (Kan. App.
2006) (unpublished opinion), in which two police officers arrived at Riley's home to
investigate a complaint unrelated to the smell or use of marijuana. After entering with the
homeowner's consent, they smelled a burnt marijuana odor and obtained a search warrant
based on the odor. Relying on MacDonald, the Riley panel held "Kansas law establishes
that such odor detected by an experienced law enforcement officer can provide sufficient
probable cause to support a search." 2006 WL 90089, at *3.

The Hubbard panel also considered State v. Ibarra, 282 Kan. 530, 147 P.3d 842
(2006), in which the court held the odor of ether, standing alone, did not constitute
probable cause to justify a vehicle's warrantless search. 282 Kan. at 543. The Hubbard
panel observed that the Ibarra court "focused on the fact that ether is a legal substance
and '[t]he strong odor of ether emanating from a house or vehicle is as consistent with
lawful activity as it is with criminal activity.'" Hubbard, 2016 WL 1614177, at *6
(quoting Ibarra, 282 Kan. at 543). The panel noted marijuana is not a substance that may
be legally possessed in Kansas, so its odor was inconsistent with lawful activity. 2016
WL 1614177, at *6.

Hubbard cites the same cases listed in Huff without supplying further analysis. But
none explicitly rejects the position that smell alone is sufficient for probable cause.
Rather, in each case, the court found probable cause relying on more than just smell
because additional incriminating evidence was present. For example, in United States v.
Kerr, 876 F.2d 1440, 1442-45 (9th Cir. 1989), the police relied on more than just smell,
but the Ninth Circuit panel stated "[b]y far the most incriminating piece of evidence was
the odor of marijuana emanating from Kerr's premises," even though the officer claimed
to smell marijuana from more than 50 yards away. 876 F.2d at 1444. Citing to the Court's
Johnson opinion, Kerr opined that even without additional evidence "the presence of the
23

 odor of contraband may itself be sufficient to establish probable cause." Kerr, 876 F.2d at
1445.

We hold that the totality of the circumstances surrounding a law enforcement
officer's detection of the smell of raw marijuana emanating from a residence can supply
probable cause to believe the residence contains contraband or evidence of a crime. See
State v. Howard, 305 Kan. 984, 990, 389 P.3d 1280 (2017) (noting probable cause for
search exists when totality of circumstances indicate fair probability location contains
contraband or evidence of a crime, including all information in officer's possession, fair
inferences from it, and any other relevant facts); State v. Hicks, 282 Kan. 599, 147 P.3d
1076 (2006). Such circumstances include, but are not limited to, proximity to the odor's
source, reported strength of the odor, experience identifying the odor, elimination of
other possible sources of the odor, and the number of witnesses testifying to the odor's
presence. This is ultimately a case-by-case determination based on the circumstances.
Not all cases relying on odor will have the same result.

We further hold the district court did not err when it concluded the officers had
probable cause to believe contraband or evidence of a crime were in Hubbard's
apartment. Both testified they detected raw marijuana odor. Nicholson testified she was
only about 2 feet from Hubbard's front door when she smelled the odor coming from the
apartment. Ivener also detected the odor and characterized it as "strong" and "potent."
And the court accepted Nicholson's training and experience in detecting both raw and
burnt marijuana in its ruling. As to Hubbard's concerns that the officers' sense of smell
was skewed by bias, inaccuracies, or ill-intent, or unbelievable because the marijuana
was discovered in a bedroom safe, those contentions were resolved by the district court's
findings and its credibility determinations inherent in those findings.

24

 Threat of evidence destruction was an exigent circumstance
To satisfy the second half of the exception for warrantless entry based on probable
cause plus exigent circumstances, an exigent circumstance exists when there is "an
objectively reasonable belief that an emergency situation exists." State v. Campbell, 297
Kan. 273, 280, 300 P.3d 72 (2013). On review, the State must rely on preventing the loss
or destruction of evidence as its exigent circumstance because it did not cross-petition for
review of the panel's rejection of its officer safety argument.

Exigent circumstances include situations in which the police reasonably
determine, from the surrounding circumstances, that the evidence will be destroyed or
concealed before a search warrant can be obtained. State v. Hardyway, 264 Kan. 451,
464-65, 958 P.2d 618 (1998). But this does not stretch to situations when only a mere
possibility of that danger exists. State v. Fewell, 286 Kan. 370, 385, 184 P.3d 903 (2008).

In its review, the Hubbard panel looked to another Court of Appeals decision,
State v. Dugan, 47 Kan. App. 2d 582, 605, 276 P.3d 819 (2012), which relied on
authority from the Fourth and Fifth Circuit Courts of Appeals to more specifically outline
the exigent circumstances factors applicable to a warrantless entry for evidence
preservation. 2016 WL 1614177, at *9. The Dugan factors are:

"(1) the time needed to secure a search warrant; (2) the reasonableness of the officers'
belief the evidence may be immediately lost; (3) potential danger to the officers guarding
the site while awaiting a warrant; (4) whether those persons with possession of the
evidence are aware of the officers' presence; and (5) the ease with which the evidence
might be destroyed or hidden. United States v. Moses, 540 F.3d 263, 270 (4th Cir. 2008);
United States v. Vega, 221 F.3d 789, 800 (5th Cir. 2000)." Dugan, 47 Kan. App. 2d at
605.

25

 We note those factors differ somewhat from Huff, which involved entry into a
residence to make a warrantless arrest. The parties provide little guidance on whether the
Dugan factors are preferable to those in Huff, but we perceive no substantive conflict.
Huff expressly notes its listing is nonexclusive and recognizes the possibility of the
evidence's loss or destruction as one of the factors to be considered. Huff, 278 Kan. at
220. We will apply the Dugan factors since they are more precisely tailored to Hubbard's
case and consistent with Huff.

The panel focused on the second, fourth, and fifth Dugan factors. Under the
second, the court highlighted Ivener's testimony that he did not know how many people
had been in the apartment originally and whether they all left, so the officers could not
know whether everyone was out. This weighs in the State's favor. Under the fourth factor,
the panel noted there was evidence the occupants were aware of the officers' presence, so
this also weighs in the State's favor because it demonstrates anyone staying behind would
be alerted to the likelihood of an impending search.

The fifth factor is most persuasive in the State's favor because drugs are relatively
easy to dispose of. 2016 WL 1614177, at *10. In Dugan, the incriminating evidence was
collision damage on the defendant's vehicle. The court reasoned repairing the damage
would have been time consuming and could not have been done inconspicuously, so the
fifth factor weighed in the defendant's favor. 47 Kan. App. 2d at 605-06. In so deciding,
the court compared hiding the vehicle damage with the "easily accomplished" task of
"flushing contraband down the toilet." 47 Kan. App. 2d at 605.

We hold exigent circumstances existed to support the warrantless entry.

26

 OPINION TESTIMONY
Hubbard next challenges the panel's conclusion that Nicholson's testimony about
smelling raw marijuana was to a fact, rather than an opinion subject to the admissibility
standards under K.S.A. 2015 Supp. 60-456. See Hubbard, 2016 WL 1614177, at *11-12.
Although we agree with Hubbard that the officers were giving their opinions when they
testified they smelled raw marijuana, we conclude the district court did not err by
admitting the testimony as lay opinions.

Standard of review

Whether a witness—expert or layperson—is qualified to testify as to an opinion is
to be determined by the trial court in the exercise of its discretion. State v. Sasser, 305
Kan. 1231, 1243, 391 P.3d 698 (2017) (citing Hawkinson v. Bennett, 265 Kan. 564, 592,
962 P.2d 445 [1998]). "'A trial court abuses its discretion when the act complained of "(1)
is arbitrary, fanciful or unreasonable; (2) is based on an error of law; or (3) is based on an
error of fact."'" 305 Kan. at 1243.
Discussion

The panel held Nicholson's testimony was not an opinion but about a fact because,
in its view, it was based on her personal knowledge of the odor of raw marijuana.
Hubbard, 2016 WL 1614177, at *11-12. And the panel rejected Hubbard's argument that
this fact testimony was incredible based on the journal article that he claims "disproves
the idea that human beings can detect the odor of marijuana." 2016 WL 1614177, at *12.
The panel noted the article itself did not reach that conclusion and reasoned it went only
to the weight or credibility to give Nicholson's testimony.

27

 We find some merit in Hubbard's contention that the panel erred by categorizing
the officers' testimony as fact, rather than opinion. While the panel was correct when it
noted the officers' testimony was based on their perceptions, this alone does not
comprehensively capture the distinction—if it may be so captured—between fact and
opinion testimony. Indeed, under K.S.A. 2017 Supp. 60-456,

"(a) If the witness is not testifying as an expert, the testimony in the form of
opinions or inferences is limited to such opinions or inferences as the judge finds: (1) Are
rationally based on the perception of the witness; (2) are helpful to a clearer
understanding of the testimony of the witness; and (3) are not based on scientific,
technical or other specialized knowledge within the scope of subsection (b).

"(b) If scientific, technical or other specialized knowledge will help the trier of
fact to understand the evidence or to determine a fact in issue, a witness who is qualified
as an expert by knowledge, skill, experience, training or education may testify thereto in
the form of an opinion or otherwise if: (1) The testimony is based on sufficient facts or
data; (2) the testimony is the product of reliable principles and methods; and (3) the
witness has reliably applied the principles and methods to the facts of the case."
(Emphasis added.)

Surely, the officers' opinions that they smelled raw marijuana were rationally
based on their perceptions because they observed an odor. The rub is whether their ability
to identify marijuana odor—based on their testimony that this facility comes from their
training and experience as police officers—propels their testimony into the realm of
expert opinion.

Recently, our court wrestled with the distinction between lay and expert opinion
testimony. In Sasser, a divided court held there was no abuse of discretion permitting a
lay witness to testify about the estimated cost of repairing a motorcycle when (1) the
witness possessed experience with motorcycle ownership and repairs, (2) his valuation of
28

 the repairs was rationally based on his perception of what he saw, and (3) his opinion
"was not based on information that was so scientific, technical, or specialized that it cried
out for greater court control . . . under [K.S.A. 2017 Supp. 60-456]." 305 Kan. at 124647. But see Sasser, 205 Kan. at 1249 (Biles, J., concurring in part and dissenting in part)
("[A] forecast of future repair costs is not an opinion 'rationally based on the perception
of the witness,' as required to make it admissible as lay opinion testimony . . . . Rather, it
is based on specialized knowledge and, therefore, is impermissible as lay opinion
testimony.").

In Sasser, the dissenting justices argued that, setting aside the witness' specialized
knowledge of motorcycle repair, the witness was not in a better position to "'draw a
legitimate conclusion from what he . . . perceived than the jury could from a narration of
the details, the details being of such character that people generally are capable of
understanding them and of arriving at a conclusion with respect thereto.'" 305 Kan. at
1249-50 (quoting 4 Gard & Casad, Kansas Law and Practice, Kan. C. Civ. Proc. Annot.
§ 60-456, p. 582 [5th ed. 2012]). And we are not alone in recognizing the difficulty
drawing sharp boundaries between lay and expert opinion testimony. See, e.g., Osbourn
v. State, 92 S.W.3d 531, 537 (Tex. Crim. App. 2002) ("A distinct line cannot be drawn
between lay opinion and expert testimony because all perceptions are evaluated based on
experiences.").

In Sasser, the critical feature for the majority that made the testimony admissible
as a lay opinion was that the special knowledge on which the motorcycle repair estimate
was based was not "so . . . specialized that it cried out for greater court control."
(Emphasis added.) Sasser, 305 Kan. at 1246. Similarly, "While smelling the odor of
marihuana smoke may not be an event normally encountered in daily life, it requires
limited, if any, expertise to identify." Osbourn, 92 S.W.3d at 537; see also In re Ondrel
M., 173 Md. App. 223, 918 A.2d 543 (2007) (holding officer's testimony that he
29

 previously smelled marijuana was sufficient foundation for officer to testify he smelled
marijuana inside a car, and testimony was a lay opinion because it was based on the
officer's perception of the odor).

The same holds true for the officers' opinions that they smelled raw marijuana in
Hubbard's case. Their specialized training on identifying that odor consisted of being
exposed to it and being told what it was. Ivener said his training was at the police
academy, and that "[t]hey did a pass-around of raw marijuana . . . so you can recognize
the odor of it." Nicholson testified to similar training but added she had detected the
smell of raw marijuana between 200 and 500 times.

We reserve some doubt this can be considered expert testimony based upon
specialized knowledge. But in this instance we are confident it is within the realm of
common human experience to smell something and subsequently be able to recognize
that same odor again, e.g., alcohol, gasoline, freshly baked bread, recently cut grass, and
so on. See State v. Loudermilk, 221 Kan. 157, 163, 557 P.2d 1229 (1976) ("Whether a
small wound is a cut or a puncture and whether it is old or new, would not appear highly
technical."). This qualifies it as lay opinion admissible under K.S.A. 2017 Supp. 60456(a).

The dissent argues the "indistinct and far less recognizable odor of raw
marijuana," as opposed to burnt marijuana, required the district court to treat the officers'
testimony as expert opinions subject to the rigors of Daubert v. Merrell Dow
Pharmaceuticals, 509 U.S. 579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993). And it is
critical of what it characterizes as our "casually intermittent factual and legal equation" of
raw marijuana odor with odors the dissent believes are more clearly recognizable. Slip
op. at 33. But the dissent does not offer any principled explanation of where the line may
be drawn between an odor distinct enough to be the subject of lay opinion testimony and
30

 one so indistinct to require expert testimony. Certainly the caselaw and the legal
authorities discussed above have not suggested any discernible demarcation. We are not
dealing with sommeliers trying to identify a white wine as a Loire Valley Chenin Blanc.

The dissent also suggests the officers were giving expert opinion testimony
because of their prior exposure to raw marijuana from their police training and on-the-job
experiences. We disagree. These officers did not learn how to smell at the police
academy. Put another way,

"There are certain fields where a witness may qualify as an expert based upon experience
and training, however, use of the terms 'training' and 'experience' do not automatically
make someone an expert. All opinions are formed by evaluating facts based on life
experiences including education, background, training, occupation, etc. While [the police
officer] may have had the potential to be qualified as an expert because she possessed
knowledge, skill, experience and education, she was not testifying as an expert when she
identified the marihuana. Rather, she was testifying based on her firsthand sensory
experiences. [The police officer] herself smelled the odor that she perceived to be burnt
marihuana. The fact that she had smelled marihuana before in the course of her
employment as a police officer does not necessarily make her an expert. And, again, even
if she was an expert, that would not preclude her from offering a lay opinion about
something she personally perceived." In re Ondrel M., 173 Md. App. 223, 244-45, 918
A.2d 543 (2007).

Admittedly, this statement from Ondrel refers to burnt marijuana, not raw
marijuana. But what forms the basis of the dissent's conclusion that raw marijuana is any
less susceptible to lay witness identification based on prior exposure than burnt
marijuana? Cf. United States v. Downs, 151 F.3d 1301, 1303 (10th Cir. 1998) ("In a case
involving raw marijuana, this court has held that 'the odor of marijuana alone can satisfy
the probable cause requirement to search a vehicle or baggage.'"); State v. Cuong Phu Le,
463 S.W.3d 872, 878 (Tex. Crim. App. 2015) (relying on officer's affidavit statements
31

 that he smelled raw marijuana at residence's front door, on defendant's person, and in
defendant's car in holding affidavit supplied probable cause for search warrant). The
answer appears to be the dissent's own uncertainty about human ability to detect the smell
and various conditions that might affect an ability. But there is nothing in the record, or in
any authority cited by the dissent, to raise this beyond speculation.

And were we free to assess the facts ourselves, this information might have been
useful in evaluating the officers' testimony. To be sure, Hubbard was free to introduce
expert testimony to undermine the officers' credibility. See United States v. Johnson, 445
Fed. Appx. 311, 312 (2011) (unpublished opinion) (defense expert on the sense of smell
testified it would be nearly impossible for officer to smell marijuana emitting from closed
bag in trunk of car due to the packaging and prevailing weather conditions); State v.
Brinkley, No. 1204003639, 2013 WL 1225869, at *5 (Del. Super. 2013) (unpublished
opinion) (defense experts testified to undermine credibility of officer's testimony that he
smelled marijuana as he approached defendant's vehicle). Hubbard did not do that.
Hubbard was also free to present evidence or cross-examine to vigorously probe the
inquiries raised by the dissent. See slip op. at 36-37. He did not do that either.

Hubbard's basis for attacking the officers' testimony was simply to include with
his pleadings a scholarly article about smell testing and disparage their credibility. And,
as discussed above, the district court found unpersuasive the conclusions reached in "the
controlled environs of the scientific study on which the defendant urge[d] the court to
rely." The dissent criticizes the district court's dismissal of this article for relying on
"unknown variables" but really all the district court did was resolve the facts in the State's
favor. As previously mentioned, on appeal we do not reweigh the evidence, assess
witness credibility, or resolve evidentiary conflicts. State v. Brown, 306 Kan. 1145, 1151,
401 P.3d 611 (2017).
32

 The district court did not abuse its discretion admitting the testimony.

Affirmed.

***

BEIER, J., dissenting: I respectfully dissent from the result and rationale of the
majority.

I have several bothers—including but not limited to the majority's casually
intermittent factual and legal equation of the distinct and recognizable odors of burnt
marijuana, "alcohol, gasoline, freshly baked bread, recently cut grass, and so on" with the
indistinct and far less recognizable odor of raw marijuana—but I will focus on only two
of my bothers, either of which would be determinative and require a different outcome.

I would hold that the district judge applied the wrong legal standard in admitting
and considering the testimony of the two law enforcement officers at the suppression
hearing, treating their expert opinions on the source of the odor they perceived as facts. I
would also hold that the judge erred in relying in part upon an absence of evidence from
the State, which bore the burden of proving the lawfulness of the sweep of defendant
Lawrence D. Hubbard's apartment, rather than evidence admitted by the State in arriving
at her conclusion that the sweep was justified by the existence of probable cause and
exigent circumstances. I discuss the errors in this order.

At the suppression hearing, the clear and uncontroverted testimony of both police
officers was that they relied on their law enforcement training and experience to arrive at
what the majority recognizes as their shared opinions that the odor of raw marijuana
33

 emanating from the defendant's apartment existed and that it was "potent" or "strong,"
even "overwhelming."

In turn, the district judge explicitly relied on the officers' training and experience
in her ruling on the motion to suppress. Her findings of fact included: "As part of her law
enforcement training and while in her official capacity, Officer [Kimberley] Nicholson
has detected the smell of raw marijuana 200 to 500 times and burnt MJ 100 to 300
times," and, "When the apartment door was opened and closed, the officers smelled what
they identified as the odor of raw marijuana coming from the apartment. Officer [Ronald]
Ivener testified the smell was 'potent' and 'overwhelming.'" She concluded that probable
cause existed as a matter of law because of the odor of raw marijuana detected by the
officers and gave no weight to a scholarly article admitted by the defense in part because
"[t]his case involves officers who are trained in the detection of marijuana odors."

The district judge again relied on the officers' training when denying the
defendant's motion for reconsideration of the suppression ruling. As the majority quotes
her,

"[Nicholson's] not an expert in the field of odors. She's not an expert in marijuana, but
she does have training. And there are numerous cases that allow for officers to testify
based on their individual personal observations and their training just to become a police
officer, and she's testified to that, and this court is aware of that training. I find her
training was sufficient. It goes more to the weight that her testimony gives and not the
admissibility of it." Slip op. at 8.

The majority ultimately expresses uncertainty whether the officers' opinions
qualified as lay or expert opinions, apparently defaulting to the former classification
because the odor of burnt marijuana has been held to be distinct enough to be easily
identified by a lay person by the Texas Court of Criminal Appeals, see Osbourn v. State,
34

 92 S.W.3d 531, 537 (2002), and because it believes that the odor of raw marijuana can be
recognized on any encounter subsequent to the officers' brief exposure to a small amount
of the known substance for a few minutes in law enforcement training years before.

I do not share the majority's uncertainty about whether the officers' opinions
qualified as expert testimony. The Court of Appeals panel erred by ruling that K.S.A. 60419, which is merely a general witness statute that allows testimony based on
"experience, training or education if such be required," was controlling. The majority
improves only marginally upon the panel's analysis by recognizing that the more specific
statute on opinion testimony, K.S.A. 2017 Supp. 60-456, controls; but it nevertheless errs
by relying upon subsection (a) on lay opinion.

The controlling provision actually is subsection (b) of K.S.A. 2017 Supp. 60-456.
The officers in this case were not testifying as mere lay persons. On the contrary, they
specifically stated that the origin of their ability to smell and identify the source of their
olfactory perception as raw marijuana stemmed from their brief exposure to the identified
odor during their study at one or more police academies, followed by their experience
with numerous cases in which they had successfully detected the substance. This
uncontroverted dependency between the officers' training and experience on the one hand
and the opinions they expressed on the other hand qualified their testimony about
detecting the strong, potent, or overwhelming odor of raw marijuana as expert opinion
testimony. As the author of today's majority opinion recently wrote in his concurring and
dissenting opinion in State v. Sasser, 305 Kan. 1231, 1249, 391 P.3d 698 (2017) (Biles,
J.): "[W]e should all understand that lay opinion testimony is not based on specialized
knowledge."

As urged by the defense, the science, if any, behind the officers' apparently sincere
belief in their professed ability to detect an odor of raw marijuana should have been
35

 subjected to vetting under the rule of Daubert v. Merrell Dow Pharmaceuticals, 509 U.S.
579, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993), which is now codified in subsection (b).
The officers' expert opinion testimony should have been admitted on the critical issue of
the existence of probable cause at the time of the sweep of the apartment only if "(1) [t]he
testimony [was] based on sufficient facts or data; (2) the testimony [was] the product of
reliable principles and methods; and (3) the witness[es] ha[d] reliably applied the
principles and methods to the facts of the case." K.S.A. 2017 Supp. 60-456(b). The
district judge erred by failing to exercise her gatekeeping function under subsection (b).

The judge's second error was her explicit reliance on "unknown variables" in this
case to disregard the scholarly article about odor testing admitted into evidence by the
defense. The State cannot meet its burden to demonstrate the lawfulness of a search or
seizure with an absence of evidence. See State v. Cleverly, 305 Kan. 598, 611, 385 P.3d
512 (2016). It must affirmatively muster evidence to support its position. Speculation is
insufficient. The judge erred when she relied in part on what the State did not show in
order to rule as she did.

This second error is in certain respects an artifact of the first. Had the district judge
engaged in the gatekeeping function demanded by subsection (b) of K.S.A. 2017 Supp.
60-456, then many of the "unknown variables" she referenced in her denial of the
suppression motion probably would not have been unknown at all.

In order to support the soundness of the science underlying the expert opinions it
sought to admit into evidence on the probable cause question, the State would have been
called upon to answer questions such as: How much raw marijuana must be present in
order for a human to be able to detect its odor? How close must the person be to the raw
marijuana in order to detect its odor? Does it make a difference whether the raw
marijuana is in a closed container or a closed container within a closed container? How
36

 long does the odor of raw marijuana linger? Does the temperature of the area in which the
marijuana is detected matter? How about the humidity? Does the presence of an odor of
burnt marijuana affect a person's ability to smell raw marijuana? How likely is it that
confirmation bias from a search that turns up raw marijuana can pollute even the most
honest perception or its later recollection or description? It nearly goes without saying
that such information would not only have been useful in evaluating the soundness of the
scientific underpinning of the officers' expert opinions but also, if the opinions were
ultimately admitted, in determining the merits of the probable cause issue.

Given the district judge's legal errors described above, I would reverse Hubbard's
convictions and vacate his sentence. This case should be remanded to the district court to
conduct a new evaluation of the defense suppression motion under the correct governing
law and any further necessary proceedings.

ROSEN, J., and JOHNSON, J., join in the foregoing dissent.

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