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SJC-11481

COMMONWEALTH vs. MATTHEW W. OVERMYER.

Berkshire. March 3, 2014. - July 9, 2014.

Present: Ireland, C.J., Cordy, Botsford, Gants, Duffly,

& Lenk, JJ.

Controlled Substances. Narcotic Drugs. Constitutional Law, 

Narcotic drugs, Search and seizure, Reasonable suspicion, 

Probable cause. Probable Cause. Search and Seizure, Motor 

vehicle, Reasonable suspicion, Probable cause.

Complaint received and sworn to in the Pittsfield Division 

of the District Court Department on May 21, 2012.

A pretrial motion to suppress evidence was heard by Jacklyn 

M. Connly, J.

An application for leave to prosecute an interlocutory 

appeal was allowed by Cordy, J., in the Supreme Judicial Court 

for the county of Suffolk, and the appeal was reported by him to 

the Appeals Court. The Supreme Judicial Court on its own 

initiative transferred the case from the Appeals Court.

John P. Bossé, Assistant District Attorney, for the 

Commonwealth.

Janet H. Pumphrey for the defendant.

The following submitted briefs for amici curiae:

Ester J. Horwich & Justin R. Dashner for Committee for 

Public Counsel Services.
2

Steven S. Epstein & Marvin Cable for National Organization 

for the Reform of Marijuana Laws.

LENK, J. In Commonwealth v. Cruz, 459 Mass. 459, 472 

(2011) (Cruz), we held that, in the wake of the 2008 ballot 

initiative decriminalizing possession of one ounce or less of 

marijuana (2008 initiative), "the odor of burnt marijuana alone 

cannot reasonably provide suspicion of criminal activity." This 

case requires us to resolve a question not explicitly answered 

in Cruz, supra: whether the smell of unburnt, as opposed to 

burnt, marijuana suffices to establish probable cause to believe 

that an automobile contains criminal contraband or evidence of a 

crime.1 Here, where police searched the defendant's vehicle 

after seizing a "fat bag" of marijuana from the glove 

compartment, and after perceiving an odor of unburnt marijuana, 

we hold that such odor, standing alone, does not provide 

probable cause to search an automobile. Because it is not clear 

on this record, however, whether police had probable cause to 

arrest the defendant for criminal possession of marijuana on the 

basis of the marijuana seized from the glove compartment, we 

remand the matter to the District Court for further proceedings 

on that issue.

1 We acknowledge the amicus briefs submitted by the 

Committee for Public Counsel Services and the National 

Organization for the Reform of Marijuana Law on behalf of the

defendant.

 
3

1. Background. We summarize the facts found by the judge 

after an evidentiary hearing on the defendant's motion to 

suppress marijuana found in his vehicle and statements made to 

police, supplemented by uncontested facts in the record. See 

Commonwealth v. Isaiah I., 448 Mass. 334, 337 (2007), S.C., 450 

Mass. 818 (2008). Two Pittsfield police officers testified at 

the hearing.

On May 19, 2012, at approximately 4:30 P.M., Officers Sean 

Klink and James McIntyre of the Pittsfield police department 

responded to the scene of a motor vehicle collision. They 

observed that the vehicle operated by the defendant, a Volvo, 

had rear-ended a minivan. After seeking to assure the wellbeing of the occupants of the minivan, the officers turned their 

attention to the defendant, who was seated at the side of the 

road.

Both officers noticed a very strong odor of unburnt 

marijuana near the location of the Volvo, and Klink asked the 

defendant if any was present in his vehicle. Acknowledging that 

there was marijuana in the Volvo, the defendant gave Klink the 

keys to the glove compartment. Klink found what he described as 

a "fat bag" of marijuana, which was "rather large," inside the 

glove compartment.2

2 There was no evidence before the judge as to the actual 

weight of the marijuana found in the "fat bag."

 
4

After retrieving the bag from the glove compartment, the 

officers still perceived a strong smell of marijuana, and, based 

on their training and experience,3 believed that an unspecified 

amount of marijuana remained present in the Volvo. The officers 

In cases where the weight of seized marijuana is not 

immediately evident, we note that the Executive Office of Public 

Safety and Security has advised that, if

"portable scales are not available, [police] have the 

option of taking the suspect's information and 

releasing him while also instructing him that he will 

receive something in the mail. When police return to 

the station, they may weigh the marijuana. If the 

weight is more than an ounce, the suspect may be 

summonsed to court on a criminal complaint. If the 

weight is an ounce or less, a citation may be mailed 

to the suspect within [fifteen] days of the offense."

Question 2 Law Enforcement Q&A, Executive Office of Public 

Safety and Security (2014), at 

http://www.mass.gov/eopss/law-enforce-and-cj/lawenforce/question-2-law-enforcement-q-and-a.html (last 

viewed July 7, 2014).

3 Pittsfield police Officer James McIntyre testified that he 

had been exposed to the odors of both burnt and unburnt 

marijuana during training at the police academy, and that he had 

completed two three-week assignments with the Pittsfield police 

drug enforcement unit during his twenty-five years as a police 

officer. He also had assisted with at least one dozen arrests 

involving marijuana, and is familiar with the smell of the 

substance based on the proximity of his desk at the police 

station to the drug evidence lockers.

Pittsfield police Officer Sean Klink testified that he had 

completed drug training at the police academy as well as 

training with the Pittsfield police department that consisted of 

"go[ing] inside [the] drug evidence locker with drug detectives 

and learn[ing] about the different drugs." In his five years as 

a police officer, Klink had participated in the execution of 

about ten search warrants involving marijuana and had carried 

out more than twenty "arrests in general."

 
5

did not observe anything else indicating the presence of 

marijuana. Klink gave the defendant Miranda warnings before 

asking whether the vehicle contained additional marijuana. The 

defendant denied that it did, but eventually admitted that there 

was more marijuana in the Volvo after Klink "intimat[ed] that a 

[canine] unit would be on its way." Klink later placed the 

defendant under arrest and took him into custody; the 

defendant's vehicle was towed to the police station.

At some point,4 McIntyre located a backpack on the back seat 

of the vehicle. The backpack contained two large freezer bags, 

which in turn contained smaller, individually wrapped packages 

of marijuana. A criminal complaint issued against the defendant 

two days later, charging him with possession of marijuana with 

intent to distribute, G. L. c. 94C, § 32C (a), and commission of 

this offense within a school or park zone, G. L. c. 94C, § 32J.

The judge determined that the strong odor of unburnt 

marijuana initially perceived by police "triggered a suspicion" 

that more than one ounce was present in the vehicle, such that 

Klink was warranted in asking the defendant whether he possessed 

4 The record is unclear whether the officers searched the 

back seat of the Volvo before or after the defendant's admission 

that the vehicle contained more marijuana, or his eventual 

arrest. The judge noted that it was "unclear from [the 

officers'] testimony when the defendant admitted there was more 

marijuana in relation to when McIntyre went into the car, but it 

[was] clear [the defendant] was detained further after the 

marijuana in the glove box was found."

 
6

marijuana, and in retrieving the "fat bag" from the glove 

compartment at the defendant's direction. Therefore, the judge 

denied the defendant's motion to suppress as to the "fat bag."

The judge also ruled that, once the defendant turned over 

the "fat bag" from the glove compartment, the officers were not 

justified in searching the back seat of the defendant's vehicle. 

"There [were] no other articulable facts to base a reasonable 

suspicion that the defendant was engaged in criminal activity, 

or that there were other drugs present"; the defendant made no 

suspicious gestures, and there were no other indicia of the sale 

or manufacturing of marijuana.5

 Thus, the judge decided that the 

officers' disbelief of the defendant's denials that there was 

additional marijuana in the vehicle was a "hunch," invalidating 

the ensuing search of the back seat of the vehicle. As a 

result, she ordered suppressed the bags of marijuana found in 

the backpack, as well as the defendant's statements to police 

after the discovery of the backpack.

The single justice allowed the Commonwealth's application 

for leave to pursue an interlocutory appeal to the Appeals 

Court, and we transferred the matter to this court on our own 

motion.

5 The judge made no findings whether the officers reasonably 

believed that the "fat bag" contained more than one ounce of 

marijuana.

 
7

2. Discussion. The Commonwealth argues that the smell of 

marijuana supported probable cause to search the back seat of 

the defendant's vehicle, rendering the search proper under the 

automobile exception to the warrant requirement.6 The 

Commonwealth contends that these circumstances differ from those 

in Cruz, supra, because that case involved the smell of burnt 

marijuana, whereas the officers in this case perceived an odor 

of unburnt marijuana.

Under the automobile exception to the warrant requirement, 

a warrantless search of an automobile is constitutionally 

permissible if the Commonwealth proves that officers had 

probable cause to believe that there was contraband or specific 

evidence of a crime in the vehicle. See Commonwealth v. Daniel, 

464 Mass. 746, 750-751 (2013); Commonwealth v. Motta, 424 Mass. 

117, 122 (1997). However, the "'ultimate touchstone' of both 

the Fourth Amendment [to the United States Constitution]and art. 

14 [of the Massachusetts Declaration of Rights] is 

reasonableness," Commonwealth v. Entwistle, 463 Mass. 205, 213 

(2012), cert. denied, 133 S. Ct. 945 (2013), quoting 

Commonwealth v. Townsend, 453 Mass. 413, 425 (2009). We have 

6 Because reasonable suspicion is a less demanding standard 

than probable cause, see Commonwealth v. Smigliano, 427 Mass. 

490, 492 (1998), implicit in the judge's finding that the 

officers lacked a reasonable suspicion that the defendant was 

engaged in criminal activity is that they also lacked probable 

cause to search the vehicle under the automobile exception to 

the warrant requirement.

 
8

determined that "[i]t is unreasonable for the police to spend 

time conducting warrantless searches for contraband when no 

specific facts suggest criminality." Cruz, supra at 477. 

Because the 2008 initiative reclassified possession of one ounce 

or less of marijuana as a civil violation, and abolished the 

attendant criminal consequences, we held in Cruz, supra at 469-

472, that the odor of burnt marijuana alone no longer 

constitutes a specific fact suggesting criminality. 

Accordingly, such an odor alone does not constitute probable 

cause to believe that a vehicle contains a criminal amount of 

contraband or specific evidence of a crime, such that the 

automobile exception to the warrant requirement may be invoked. 

See Commonwealth v. Daniel, supra at 750-752; Cruz, supra at 

475-476.

Here, the judge found that the odor of unburnt marijuana 

did not justify the officers' search of the back seat of the 

vehicle. The judge determined that, once the defendant 

surrendered the "fat bag" of marijuana from the glove 

compartment, the officers' belief that there was more to be 

found in the vehicle was merely a "hunch." There was nothing to 

suggest that the marijuana in the "fat bag" did not itself 

account for the smell the officers perceived. Although the 

Commonwealth argues, quoting Commonwealth v. Skea, 18 Mass. App. 

Ct. 685, 690 n.8 (1984), that "[i]t is widely accepted that the 
9

discovery of some controlled substances gives probable cause to 

search for additional controlled substances in the vicinity," 

our decisions since 2008 have rejected that proposition as to 

marijuana. See Commonwealth v. Pacheco, 464 Mass. 768, 771-772 

(2013) (presence of less than one ounce of marijuana in vehicle 

did not give rise to probable cause to search it for additional 

marijuana); Commonwealth v. Jackson, 464 Mass. 758, 766 (2013) 

(observation of defendant with marijuana cigarette did not give 

rise to probable cause to search person); Commonwealth v. 

Daniel, supra at 751-752 (defendant's surrender of two small 

bags of marijuana totaling less than one ounce did not give rise 

to probable cause to search vehicle);.

Massachusetts cases since 2008 also have recognized the 

dubious value of judgments about the occurrence of criminal 

activity based on the smell of burnt marijuana alone, given that 

such a smell points only to the presence of some marijuana, not 

necessarily a criminal amount.7 See Commonwealth v. Pacheco, 

supra at 771-772; Commonwealth v. Daniel, supra at 750-752; 

Cruz, supra at 472; Commonwealth v. Fontaine, 84 Mass. App. Ct. 

7

 General Laws c. 94C, § 32L, provides in relevant part:

"Notwithstanding any general or special law to 

the contrary, possession of one ounce or less of 

marihuana shall only be a civil offense, subjecting an 

offender who is eighteen years of age or older to a 

civil penalty of one hundred dollars and forfeiture of 

the marihuana, but not to any other form of criminal 

or civil punishment or disqualification."

 
10

699, 706 (2014). Although the odor of unburnt, rather than 

burnt, marijuana could be more consistent with the presence of 

larger quantities, see Cruz, supra at 469 n.15, citing 

Commonwealth v. MacDonald, 459 Mass. 148, 150-153 (2011), it 

does not follow that such an odor reliably predicts the presence 

of a criminal amount of the substance, that is, more than one 

ounce, as would be necessary to constitute probable cause. See 

Commonwealth v. Antobenedetto, 366 Mass. 51, 56 n.2 (1974) ("The 

foundation of probable cause must be specific data, the 

reliability of which could be judged by a magistrate").

The officers in this case detected what they described as a 

"strong" or "very strong" smell of unburnt marijuana. However, 

such characterizations of odors as strong or weak are inherently 

subjective; what one person believes to be a powerful scent may 

fail to register as potently for another. See Doty, Wudarski, 

Marshall, & Hastings, Marijuana Odor Perception: Studies 

Modeled from Probable Cause Cases, 28 Law & Hum. Behav. 223, 232 

(2004) (identifying traits such as gender and age that may 

influence ability to smell). Moreover, the strength of the odor 

perceived likely will depend on a range of other factors, such 

as ambient temperature, the presence of other fragrant 

substances, and the pungency of the specific strain of marijuana 

present. See State v. Pollman, 286 Kan. 881, 894 (2008) ("the 

strength of the smell is subjective and also depends on factors 
11

such as masking agents [chewing gum, mints, tobacco products] 

and the environment where the odor is detected"); Doty, 

Wudarski, Marshall, & Hastings, supra at 231-232 (participants 

in experiment displayed weaker ability to detect odor of 

immature female marijuana plant as compared to that of mature 

plant, and ability to discern smell was affected by presence of 

diesel exhaust fumes; temperature also can influence potency of 

odor perceived). As a subjective and variable measure, the 

strength of a smell is thus at best a dubious means for reliably 

detecting the presence of a criminal amount of marijuana.

Although it is possible that training may overcome the 

deficiencies inherent in smell as a gauge of the weight of 

marijuana present, see Doty, Wudarski, Marshall, & Hastings, 

supra at 232, there is no evidence that the officers here had 

undergone specialized training that, if effective, would allow 

them reliably to discern, by odor, not only the presence and 

identity of a controlled substance, but also its weight. 

Indeed, in somewhat related cases that turn on the sense of 

smell, such as those involving canine alerts and canine tracking 

evidence, we have required that a sufficient foundation be laid 

as to the canine's ability before the evidence may be admitted

at trial. See Commonwealth v. Taylor, 426 Mass. 189, 197-198 

(1997) (canine tracking evidence properly admitted where 

appropriate foundation established its reliability); 
12

Commonwealth v. LaPlante, 416 Mass. 433, 440 n.10 (1993) 

(sufficient foundation for consideration of canine tracking 

evidence includes qualifications of handlers and canines, their 

training, and number of successful tracks). Similarly, Federal 

courts, including the United States Supreme Court, have required 

that probable cause determinations based on canine alerts be 

supported by evidence of the canine's reliability. See Florida

v. Harris, 133 S. Ct. 1050, 1057-1058 (2013) (court can presume 

that dog's alert provides probable cause to search "[i]f a bona 

fide organization has certified a dog after testing his 

reliability in a controlled setting," but defendant must be 

given opportunity to challenge evidence of dog's reliability); 

United States v. Owens, 167 F.3d 739, 749 (1st Cir.), cert. 

denied, 528 U.S. 894 (1999), citing United States v. Race, 529 

F.2d 12, 14 (1st Cir. 1976) ("The existence of probable cause 

based on an alert by a drug dog depends upon the dog's 

reliability").

In sum, we are not confident, at least on this record, that 

a human nose can discern reliably the presence of a criminal 

amount of marijuana, as distinct from an amount subject only to 

a civil fine. In the absence of reliability, "a neutral 

magistrate would not issue a search warrant, and therefore a 

warrantless search is not justified based solely on the smell of 
13

marijuana," whether burnt or unburnt. Commonwealth v. Daniel, 

supra at 751, citing Cruz, supra at 475-476.

The judge correctly determined, therefore, that the odor of 

unburnt marijuana did not justify the search of the back seat of 

the defendant's vehicle under the automobile exception to the 

warrant requirement. However, she did not specifically address 

whether the seizure of the "fat bag," if reasonably thought to 

weigh more than one ounce, would support probable cause to 

arrest the defendant, thereby providing an independent basis for 

the warrantless search. See Commonwealth v. Perkins, 465 Mass. 

600, 605 (2013), quoting Arizona v. Gant, 556 U.S. 332, 346 

(2009) (police may search automobile incident to arrest of its 

driver where arrestee "is within reaching distance of the 

vehicle or it is reasonable to believe the vehicle contains 

evidence of the offense of arrest"). In this regard, the judge 

did not make findings necessary to a determination whether there 

was probable cause to arrest the defendant for possession of the 

"fat bag," including whether the officers had a reasonable 

belief that the "fat bag" contained more than one ounce of 

marijuana.8

3. Conclusion. The order allowing the defendant's motion 

to suppress is vacated. The case is remanded to the District

Court for a determination, after any hearings the judge deems 

8 See note 2, supra.

 
14

necessary, whether the officers had probable cause to arrest the 

defendant on the basis of the marijuana seized from the glove 

compartment.

So ordered.