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SJC-11967
COMMONWEALTH vs. THOMAS J. GERHARDT.
Worcester. January 6, 2017. - September 19, 2017.
Present: Gants, C.J., Lenk, Hines, Gaziano, Lowy, & Budd, JJ.1
Marijuana. Motor Vehicle, Operating under the influence.
Evidence, Field sobriety test.
Complaint received and sworn to in the Worcester Division
of the District Court Department on April 24, 2013.
A motion for a hearing to challenge the admissibility of
certain evidence was heard by Andrew M. D'Angelo, J., and
questions of law were reported by him to the Appeals Court.
The Supreme Judicial Court granted an application for
direct appellate review.
Rebecca A. Jacobstein, Committee for Public Counsel
Services, for the defendant.
Michelle R. King, Assistant District Attorney, for the
Commonwealth.
Steven S. Epstein & Marvin Cable, for National Organization
for the Reform of Marijuana Laws, amicus curiae, submitted a
brief.
Michael A. Delsignore & Julie Gaudreau, for National
College for DUI Defense, amicus curiae, submitted a brief.
1
Justice Hines participated in the deliberation on this
case prior to her retirement.
2
GAZIANO, J. In this case we are asked to consider the
admissibility of field sobriety tests (FSTs) where a police
officer suspects that a driver has been operating under the
influence of marijuana. Police typically administer three
FSTs -- the "horizontal gaze nystagmus test," the "walk and turn
test" and the "one leg stand test" -- during a motor vehicle
stop in order to assess motorists suspected of operating under
the influence of alcohol or other drugs. These tests were
developed specifically to measure alcohol consumption, and there
is wide-spread scientific agreement on the existence of a strong
correlation between unsatisfactory performance and a blood
alcohol level of at least .08%.
By contrast, in considering whether a driver is operating
under the influence of marijuana, there is as yet no scientific
agreement on whether, and, if so, to what extent, these types of
tests are indicative of marijuana intoxication. The research on
the efficacy of FSTs to measure marijuana impairment has
produced highly disparate results. Some studies have shown no
correlation between inadequate performance on FSTs and the
consumption of marijuana; other studies have shown some
correlation with certain FSTs, but not with others; and yet
other studies have shown a correlation with all of the most
frequently used FSTs. In addition, other research indicates
3
that less frequently used FSTs in the context of alcohol
consumption may be better measures of marijuana intoxication.
The lack of scientific consensus regarding the use of
standard FSTs in attempting to evaluate marijuana intoxication
does not mean, however, that FSTs have no probative value beyond
alcohol intoxication. We conclude that, to the extent that they
are relevant to establish a driver's balance, coordination,
mental acuity, and other skills required to safely operate a
motor vehicle, FSTs are admissible at trial as observations of
the police officer conducting the assessment. The introduction
in evidence of the officer's observations of what will be
described as "roadside assessments" shall be without any
statement as to whether the driver's performance would have been
deemed a "pass" or a "fail," or whether the performance
indicated impairment. Because the effects of marijuana may vary
greatly from one individual to another, and those effects are as
yet not commonly known, neither a police officer nor a lay
witness who has not been qualified as an expert may offer an
opinion as to whether a driver was under the influence of
marijuana.2
1. Background. a. Prior proceedings. Following a motor
vehicle stop, Thomas Gerhardt was charged in the District Court
2
We acknowledge the amicus briefs in support of the
defendant submitted by the National College for DUI Defense and
the National Organization for the Reform of Marijuana Laws.
4
with operating a motor vehicle under the influence of marijuana,
in violation of G. L. c. 90, § 24. Gerhardt filed a motion for
a Daubert-Lanigan hearing, seeking to challenge the
admissibility of evidence concerning his performance on FSTs
conducted after the stop. See Daubert v. Merrell Dow Pharms.,
Inc., 509 U.S. 579, 592-595 (1993); Commonwealth v. Lanigan, 419
Mass. 15, 24-27 (1994). After an evidentiary hearing, a
District Court judge reported four questions to the Appeals
Court, pursuant to Mass. R. Crim. P. 34, as amended, 442 Mass.
1501 (2004).
"1. Whether police officers may testify to the
administration and results of standard [FSTs] in
prosecutions for [o]perating [u]nder the [i]nfluence of
[m]arijuana as they do in [o]perating [u]nder the
[i]nfluence of [a]lcohol prosecutions?
"2. Are the effects of marijuana consumption
sufficiently within the common knowledge and experience of
a lay person, such that a non-expert witness may offer
opinion evidence whether a person is 'high' on marijuana?
"3. May a police officer, who has not been qualified
as an expert witness, testify to the effects of marijuana
on a person such as bloodshot eyes, lack of coordination
and/or balance, reaction times, slow speech, paranoia, or
relaxed responses[?]
"4. May a juror rely on their own experience and
common sense about the effects of marijuana as they may do
in an [o]perating [u]nder the [i]nfluence of [a]lcohol
prosecution?" [footnote omitted].
We granted Gerhardt's application for direct appellate
review. After oral argument, we remanded the matter to the
District Court judge who had reported the questions for further
5
findings on eleven specific issues. Following the return of the
judge's findings, we again heard oral argument in the matter.
b. Facts. The parties submitted a statement of agreed
facts as to the evidence that the Commonwealth would seek to
present at trial. On February 13, 2013, at approximately
12:20 A.M., Trooper French of the State police3 observed a blue
Suzuki Grand Vitara motor vehicle traveling south on Route 146,
without the rear lights on. French followed the vehicle as it
left Route 146 at exit 8. He activated his emergency lights and
stopped the vehicle on Elmwood Street in Millbury.
French approached the vehicle on the passenger side. There
were three occupants in the vehicle: the driver, later learned
to be Gerhardt, and two passengers. French saw smoke inside the
vehicle, and, as soon as the front passenger window was lowered,
he detected "the distinct odor of burnt marijuana." He also saw
a large amount of what he identified as cigar tobacco on the
floor, and a cigar slicer on the key ring in the ignition. The
trooper asked the driver for his driver's license and
registration. Gerhardt handed him the license and said that he
did not have his registration.
French asked Gerhardt how much marijuana was in the
vehicle. Gerhardt responded that there were "a couple of
roaches" in the ashtray; he pulled two largely-consumed rolled
3
Trooper French's first name is not apparent in the record.
6
cigarettes from the ashtray and handed them to French. French
then asked when the occupants had smoked marijuana. One of the
passengers responded that they had smoked about twenty minutes
previously. Gerhardt said that it had been about three hours
earlier. French walked to the driver's side of the vehicle and
noticed that the light switch was in the "off" position. He
asked Gerhardt how much he had smoked. Gerhardt responded that
he had smoked approximately one gram of marijuana.
French then asked Gerhardt to step out of the vehicle to
perform FSTs. French administered a number of FSTs, including
the horizontal gaze nystagmus test (HGN);4 the nine-step walk-
and-turn test (WAT); and the one-leg-stand test (OLS). French
also asked Gerhardt to recite the alphabet from D to Q and to
count backward from seventy-five to sixty-two.
Gerhardt had no nystagmus indicators, and was able to
recite the requested portion of the alphabet and to count
backwards. He did not perform the WAT as instructed, even after
4
"Nystagmus is '[a]n abnormal and involuntary movement of
the eyeballs from side to side or up and down, but usually from
side to side.'" Commonwealth v. Sands, 424 Mass. 184, 186
(1997), quoting State v. Merritt, 36 Conn. App. 76, 84 (1994).
An officer administers the HGN test by having the subject focus
on a moving object and observing whether the subject is able to
follow the object smoothly with his or her eyes, whether the
subject's eyes bounce at the extremes of the field of vision,
and whether they exhibit nystagmus, where there is an angle of
less than forty-five degrees between the eyes and the object.
Sands, supra at 186-187. Introduction of the results of this
test at trial requires expert testimony. See id. at 188.
7
several explanations and a demonstration by the trooper in
response to Gerhardt's first answer in the negative when asked
whether he understood the instructions. Rather than standing
heel to toe, with his right foot in front and his left toes
touching his heel, as he had been shown, Gerhardt moved his feet
so that they were side by side; he also did not turn around as
instructed. French determined that "the results of this test
indicated that Gerhardt was impaired." The trooper then
provided instructions and gave a demonstration of the OLS test,
and Gerhard indicated that he understood. In performing the
test, however, Gerhard did not remain upright on one foot,
instead putting his foot down multiple times, and swayed.
French determined that "the results of this test indicated that
Gerhardt was impaired."
After administering these tests, French concluded that
Gerhardt was under the influence of marijuana. French informed
Gerhardt that he was not under arrest, but had him sit in the
back of French's cruiser. Both passengers were asked to step
out of the vehicle and were pat frisked. They, too, were told
that they were not under arrest, and were placed in the back
seat of the cruiser. A second trooper arrived at the scene.
During a search of the vehicle, the troopers recovered two more
marijuana "roaches" and a marijuana stem.
8
On April 24, 2013, a criminal complaint issued against
Gerhardt charging him with operating a motor vehicle while under
the influence of drugs, pursuant to G. L. c. 90,
§ 24 (1) (a) (1), and traffic violations.
2. Discussion. a. Field sobriety tests. The FSTs, which
were designed to detect alcohol impairment, are administered and
evaluated in a standardized manner. The two tests primarily
administered in the context of alcohol impairment are the WAT
and the OLS, which are designed to assess an individual's
balance, coordination, dexterity, ability to follow directions,
and ability to focus attention on multiple subjects at the same
time.5
In performing the WAT, the subject is directed to take nine
steps, walking heel-to-toe, along a real or imaginary straight
line. The subject then turns on one foot and returns in the
same manner. An officer administering the WAT looks for eight
specific indicators of impairment: losing balance while
listening to the instructions, beginning before the instructions
are finished, stopping to regain balance while walking, failing
to walk heel-to-toe, stepping off the line, using arms to
5
There are a number of other FSTs, such as the "Romberg
balance test," in which the subject stands with heels and toes
together and arms at the side of the body and tips his or her
head back slightly and estimates the passage of thirty seconds,
and the "finger to nose test," which are less frequently used in
the context of alcohol impairment.
9
balance, making an improper turn, or taking an incorrect number
of steps. Where the consumption of alcohol is at issue, there
is an established correlation between performance on the test
and blood alcohol content (BAC), with some research indicating
that as many as seventy-nine per cent of individuals who exhibit
two or more of these indicators have a BAC of 0.08 per cent or
higher.
In performing the OLS, the subject stands with one foot
raised approximately six inches off the ground while counting
aloud for thirty seconds. An officer conducting the test looks
for four indicators of impairment: swaying while balancing,
using arms to balance, hopping to maintain balance, and putting
the foot down. Research has indicated that as many as eighty-
three per cent of individuals who exhibit two or more of these
indicators have a BAC of 0.08 per cent or higher.
b. Admissibility of the FSTs in the context of marijuana.
While using marijuana is no longer a crime in Massachusetts for
adults who are at least twenty-one years old,6 operating a motor
vehicle while under the influence of marijuana remains a
criminal offense. See G. L. c. 90, § 24. In a prosecution for
operating while under the influence of marijuana, it is the
Commonwealth's burden to prove beyond a reasonable doubt, in
6
See St 2016, c. 334, "The Regulation and Taxation of
Marijuana Act."
10
addition to the other elements of the offense, that a
defendant's consumption of marijuana impaired his or her ability
to drive a motor vehicle safely. See Commonwealth v. Daniel,
464 Mass. 746, 756 (2013), quoting Commonwealth v. Connolly, 394
Mass. 169, 173 (1985) (in prosecution for operating under
influence of alcohol or marijuana, the Commonwealth "need not
prove that the defendant actually drove in an unsafe or erratic
manner, . . . [but] it must prove a diminished capacity to
operate safely").
Unlike alcohol, marijuana does not act as a general central
nervous system depressant, impairing functions throughout the
body. Nonetheless, the primary psychoactive substance in
marijuana, tetrahydrocannibol (THC), is known to have an impact
on several functions of the brain that are relevant to driving
ability, including the capacity to divide one's attention and
focus on several things at the same time, balance, and the speed
of processing information. While not all researchers agree, a
significant amount of research has shown that consumption of
marijuana can impair the ability to drive. There is ongoing
disagreement among scientists, however, as to whether the FSTs
are indicative of marijuana impairment. In recent years,
numerous studies have been conducted in an effort to determine
whether a person's performance on the FSTs is a reliable
11
indicator of impairment by marijuana.7 These studies have
produced mixed results.8 For example, researchers found that the
FSTs were mildly sensitive to the effects of marijuana, with the
OLS being the most sensitive. That study, however, also
indicated that the OLS produced numerous false positives.9 Other
researchers found that the OLS was a somewhat more reliable
indicator of marijuana impairment than the WAT.10 In a more
recent study, by contrast, a different group of researchers
found that the WAT was a better indicator of marijuana
impairment than the OLS.11 Researchers conducting another study
found that marijuana significantly impaired performance on the
7
The judge noted several of these studies in his findings
on remand from this court. In addition, both parties provided
numerous such studies in the record, and one of the amici did as
well.
8
The number of studies in this field is vast; we cite only
a few representative examples.
9
Bosker, Theunissen, Conen, Kuypers, Jeffery, Walls,
Kauert, Toennes, Moeller, & Ramaekers, A Placebo-Controlled
Study to Assess Standardized Field Sobriety Tests Performance
During Alcohol and Cannabis Intoxication in Heavy Cannabis Users
and Accuracy of Point of Collection Devices for Detecting THC in
Oral Fluid, 223 Psychopharmacology 439, 443-444 (2012) (Bosker).
10
Papafotiou, Carter, & Stough, An Evaluation of the
Sensitivity of the Standardized Field Sobriety Tests (SFSTs) to
Detect Impairment Due to Marijuana Intoxication, 180
Psychopharmacology 107, 113 (2005) (Papafotiou).
11
Declues, Perez, & Figueroa, A 2-Year Study of Delta-9-
tetrahydrocannabinol Concentrations in Drivers: Examining
Driving and Field Sobriety Test Performance, 61 J. Forensic
Sciences 1664, 1669 (2016).
12
HGN, the WAT, and the OLS.12 Other studies have shown no
correlation between performance on the HGN and consumption of
marijuana, even where the OLS or WAT showed some sensitivity to
marijuana consumption,13 while others have found no correlation
between the consumption of marijuana and any of these FSTs.14
As a result of these varied results, some researchers have
suggested development of another group of FSTs, combining the
currently less-frequently used Romberg stand test and the nose-
touch test, see note 5, supra, with a to-be-developed test on
pupil constriction,15 or adding a scoring factor of head
movements or jerks to the standard FSTs.16 Other researchers are
working on a tongue or cheek swab test that directly measures
levels of THC shortly after consumption.17 It is clear from the
above, as the judge stated in his findings on remand, that the
scientific community has yet to reach a consensus on the
12
Papafotiou, supra at 111-113.
13
Hartman, Richman, Hayes, & Heustis, Drug Recognition
Expert (DRE) Examination Characteristics of Cannabis Impairment,
92 Accident Analysis and Prevention 219, 226 (2016) (Hartman).
14
See generally Neavyn, Blohm, Babu, & Bird, Medical
Marijuana and Driving: a Review, 10 J. Med. Toxicol. 269
(2014); Jones, Donnelly, Swift, & Weatherburn, Driving Under the
Influence of Cannabis: The Problem and Potential
Countermeasures, 87 Crime & Justice Bulletin 1 (2005).
15
See Hartman, supra at 226.
16
See Papafotiou, supra at 108.
17
See Bosker, supra at 442, 445.
13
reliability of FSTs to assess whether a driver is under the
influence of marijuana.
The lack of scientific agreement, however, does not, by
itself, resolve the question whether a driver's performance on
an FST is relevant evidence in a trial on a charge of operating
under the influence of marijuana. " The relevance threshold for
the admission of evidence is low. 'Evidence is relevant if it
has a "rational tendency to prove an issue in the case,"'"
Commonwealth v. Arroyo, 442 Mass. 135, 144 (2004), quoting
Commonwealth v. LaCorte, 373 Mass. 700, 702 (1977), or to
"render a 'desired inference more probable than it would be
[otherwise],'" Arroyo, supra, quoting Commonwealth v.
Fayerweather, 406 Mass. 78, 83 (1989). To be relevant, evidence
"need not establish directly the proposition sought; it must
only provide a link in the chain of proof." Commonwealth v.
Sicari, 434 Mass. 732, 750 (2001), cert. denied, 534 U.S. 1142
(2002), quoting Commonwealth v. Yesilciman, 406 Mass. 736, 744
(1990).
The absence of scientific consensus regarding the use of
standard FSTs in attempting to evaluate marijuana intoxication
does not mean that they have no probative value. A police
officer makes numerous relevant observations in the course of an
encounter with a possibly impaired driver. There is no doubt
that an officer may testify to his or her observations of, for
14
example, any erratic driving or moving violations that led to
the initial stop; the driver's appearance and demeanor; the odor
of fresh or burnt marijuana; and the driver's behavior on
exiting the vehicle.
In our view, certain of the FSTs also may provide
information that is relevant to the question of a defendant's
impairment, and a police officer may testify, as a lay witness,
to his or her observations of the defendant's performance. In
particular, observations of the performance of the OLS and the
WAT may be admissible as evidence of a defendant's balance,
coordination, ability to retain and follow directions, and
ability to perform tasks requiring divided attention, and the
presence or absence of other skills necessary for the safe
operation of a motor vehicle.18 We see no reason why an
officer's observations of a defendant's behavior on being asked
to walk a straight line or to stand on one foot should be
18
The HGN stands on a different footing from the FSTs that
are directed to balance and coordination. We previously have
held that, in a prosecution for operating under the influence of
alcohol, "the HGN test relies on an underlying scientific
proposition and therefore expert testimony is required." See
Sands, 424 Mass. at 188. In addition, "there must be a
determination as to the qualification of the individual
administering the HGN test and the appropriate procedure to be
followed if the HGN test results are to be admitted at trial."
Id. We reached this result because the correlation between
alcohol intoxication and nystagmus is not within the common
experience of jurors. Id. In the context of marijuana, any
correlation between nystagmus and intoxication is even further
beyond jurors' common knowledge and experience.
15
excluded because the scientific community's understanding of
precisely how this correlates with marijuana use is still
evolving. We are not persuaded, however, that the FSTs can be
treated as scientific tests establishing impairment as a result
of marijuana consumption. The scientific community has not
reached a consensus as to whether a defendant's performance on
any combination of FSTs, or on any individual FST, is correlated
with marijuana use or impairment.
The unsettled state of the scientific research suggests
that FST evidence neither should be treated as a definitive test
of impairment nor excluded entirely from consideration by the
finder of fact. Cf. Commonwealth v. Thomas, 476 Mass. 451, 464
(2017) (where there is no consensus that simultaneous display of
photographs is inferior to sequential display, "the
decision . . . is best left to law enforcement, and the choice
will continue to bear on the weight of the identification, but
not on its admissibility"). Moreover, that marijuana can cause
impairment of skills necessary to driving, such as coordination,
concentration, and the ability to divide one's attention among
multiple tasks is within the common experience and knowledge of
jurors. A police officer testifying to a defendant's
performance on these FSTs therefore need not be qualified as an
expert, and such evidence may be admitted without satisfying the
Daubert-Lanigan requirements. A police officer may not suggest,
16
however, on direct examination that an individual's performance
on an FST established that the individual was under the
influence of marijuana.19 Likewise, an officer may not testify
that a defendant "passed" or "failed" any FST, as this language
improperly implies that the FST is a definitive test of
marijuana use or impairment.20
Indeed, the word "test" itself inadvertently may lend "an
aura of scientific validity." See United States v. Horn, 185 F.
Supp. 2d 530, 559 (D. Md. 2002). We recognize, nonetheless,
that it is not practicable to eliminate the concept of testing
entirely from trial testimony. The FSTs are used as means to
evaluate a defendant's ability to perform discrete tasks which
are correlated to skills required to safely drive a vehicle.
See Webster's New Universal Unabridged Dictionary 1951 (2003)
(defining "test" as, inter alia, "a set of questions, problems,
or the like, used as a means of evaluating the abilities,
19
Here, for example, a trooper testified at the motion
hearing that "the results of the [WAT and OLS] indicated that
Gerhardt was impaired." This testimony would not be admissible
at trial.
20
On cross-examination, defense counsel may challenge a
police officer's testimony concerning a defendant's performance
of an FST or any portion of an FST. See S.L. Jones, Drunk
Driving Defense, §§ 3.33-3.48 (2016-2017 ed.). See also id. at
§§ 3.49-3.54. We do not bar defense counsel from eliciting from
the officer his or her subjective evaluation of the defendant's
performance, but we stress that defense counsel makes this
strategic decision at his or her own peril, and opens the door
to redirect examination by the Commonwealth on the same topic.
17
aptitudes, skills, or performance of an individual or group;
examination," and "a set of standardized questions, problems, or
tasks designed to elicit responses for use in measuring the
traits, capacities, or achievements of an individual"). An
officer administering the WAT, for example, assesses a
defendant's ability to take nine steps, walk heel-to-toe on a
straight line, turn around, and return in the same manner. In
some sense, the officer thereby "tests" (measures, examines,
evaluates, assesses, or, at a minimum, observes) the driver's
physical balance and coordination, as well as his or her mental
ability to understand and follow directions and to perform
divided-attention tasks, albeit not in the same way that a
chemist in a laboratory tests a sample for the presence of a
particular substance. In all circumstances, however, it must be
made clear to the fact finder that the WAT, the OLS, and the
other FSTs do not directly test marijuana impairment. The FSTs
are a means of evaluating a defendant's balance, coordination,
and other skills specific to that test. In addition, a witness
testifying to the performance of FSTs in the context of
marijuana intoxication should refer to a driver's performance on
"roadside assessments," so as not to suggest that they function
as scientific validation of a defendant's sobriety or
intoxication.
18
We emphasize as well another consequence of the lack of
consensus regarding the FSTs: the fact that the FSTs cannot be
treated as scientific "tests" of impairment means that evidence
of performance on FSTs, alone, is not sufficient to support a
finding that a defendant's ability to drive safely was impaired
due to the consumption of marijuana, and the jury must be so
instructed.21
c. Lay testimony on the effects of marijuana. We also are
asked whether a police officer may testify, without being
qualified as an expert, to the effects of marijuana consumption
and may offer an opinion that a defendant was intoxicated by
marijuana. We conclude that an officer may not do so.
"A lay opinion . . . is admissible only where it is
'(a) rationally based on the perception of the witness;
(b) helpful to a clear understanding of the witness's testimony
or the determination of a fact in issue; and (c) not based on
scientific, technical, or other specialized knowledge.'"
Commonwealth v. Canty, 466 Mass. 535, 541 (2013), quoting Mass.
G. Evid. § 701 (2013). In the alcohol context, "a lay [officer]
. . . may offer his opinion regarding a defendant's level of
sobriety or intoxication but may not opine whether a defendant
operated a motor vehicle while under the influence of alcohol or
21
A model jury instruction regarding FSTs, to be used in
prosecutions for operating under the influence of marijuana, is
set forth in the Appendix.
19
whether the defendant's consumption of alcohol diminished his
ability to operate a motor vehicle safely." Canty, supra at
544, citing Commonwealth v. Jones, 464 Mass. 16, 17 n.1 (2012).
Such lay opinion testimony is proper because it is not based on
scientific, technical, or other specialized knowledge that would
require expert testimony, but, rather, lies within the realm of
common experience. We long have observed that "[t]he 'effects
of liquor upon the minds and actions of men are well known to
everybody.'" Commonwealth v. Wall, 469 Mass. 652, 671 (2014),
quoting Commonwealth v. Taylor, 263 Mass. 356, 362 (1928). See
Canty, supra at 542, quoting Holton v. Boston Elevated Ry. Co.,
303 Mass. 242, 246 (1939) ("'the principal objective symptoms
[of alcohol intoxication] are so well known' that we consider
the lay opinion to have probative value").
No such general knowledge exists, however, as to the
physical or mental effects of marijuana consumption, which vary
greatly amongst individuals. On remand, the District Court
judge reported in his findings of fact, based on expert
testimony presented by both sides and numerous scientific
studies, as well as existing case law in Massachusetts, that
"[n]o studies have concluded that any specific characteristics
are routinely found in people who have used marijuana and were
impaired. Manifestations of impairment may differ between
subjects who are under the influence of liquor and those who are
20
under the influence of marijuana, depressants, or stimulant
substances. The judge found further that some scientific
studies had identified "four prevalent physical characteristics
common among those who were determined to be cannabis-positive
drivers . . . These physical characteristics are red and/or
bloodshot eyes, a lack of convergence, eyelid tremors, and
drowsiness." He determined, however, that no testimony admitted
at the Daubert-Lanigan hearing related these physical
characteristics "to an inference of impaired driving by reason
of marijuana use. Further, no scientific studies validating
these specific physical characteristics as symptomatic of
impaired driving by reason of marijuana use were entered into
evidence." Our review of the record confirms that the judge’s
findings regarding lay opinion evidence are supported by the
documentary evidence and in the studies submitted to us.
Where there is no scientific consensus on what, if any,
physical characteristics indicate marijuana intoxication, no lay
opinion can be admissible as common knowledge or understanding
on that subject. A lay witness may testify concerning a
defendant's observable appearance, behavior, and demeanor, but
may not offer an opinion as to the defendant's sobriety or
intoxication.22 See State v. Schories, 827 N.W.2d 659, 666 (Iowa
22
We caution the Commonwealth that "a prosecutor who
elicits from a police officer his or her special training or
21
2013) (expert testimony preferred on cause of intoxication for
substances other than alcohol); State v. Noback, 309 Mont. 342,
346 (2002) ("we are not persuaded that lay people are
sufficiently knowledgeable about common symptoms of drug
consumption . . . to offer lay opinion testimony"); State v.
Bealor, 187 N.J. 574, 587 (2006) (court declined "to place lay
opinion testimony regarding marijuana intoxication on the same
footing as lay opinion testimony as to alcohol intoxication").
See also Commonwealth v. Sliech-Brodeur, 457 Mass. 300,
330 & n.43 (2010) (lay witness may not testify that individual
suffers from mental illness, but may testify to observed
behavior).
With respect to the question of jurors' use of their own
common sense, we recognize that jurors are the ultimate arbiters
of the facts. See Commonwealth v. Lykus, 367 Mass. 191, 197
(1975). As a general rule, trial judges routinely instruct
jurors, and jurors are urged by counsel, "not [to] leave their
common sense outside the jury room." See Commonwealth v.
Mutina, 366 Mass. 810, 820 (1975). Jurors may use their common
sense in evaluating whether the Commonwealth introduced
expertise in ascertaining whether a person is intoxicated risks
transforming the police officer from a lay witness to an expert
witness on this issue, and the admissibility of any opinion
proffered on this issue may then be subject to the different
standard applied to expert witnesses." See Commonwealth v.
Canty, 466 Mass. 535, 541 n.5 (2013).
22
sufficient evidence to satisfy its burden of proof. See
Commonwealth v. Cole, 380 Mass. 30, 35-36 (1980) (in context of
criminal responsibility, jurors may rely on facts and
circumstances surrounding crime to determine whether
Commonwealth established defendant's sanity). We rely on the
judge's limiting instructions to inform jurors about the proper
use of FST evidence. See Commonwealth v. Jackson, 384 Mass.
572, 579 (1981).
Conclusion. We answer the reported questions as follows:
1. "No." Police officers may not testify to the
administration and results of FSTs as they do in operating
under the influence of alcohol prosecutions. Police
officers may testify to the administration of "roadside
assessments" in the manner set forth in this opinion.
2. "No." A lay witness may not offer an opinion that
another person is "high" on marijuana.
3. "Yes." A police officer may testify to observed
physical characteristics of the driver such as blood shot
eyes, drowsiness, and lack of coordination. The officer is
not permitted to offer an opinion that these
characteristics mean that the driver is under the influence
of marijuana.
4. "Yes." Jurors are permitted to utilize their
common sense in assessing trial evidence.
The case is remanded to the District Court for further
proceedings consistent with this opinion.
So ordered.
Appendix.
Model Jury Instruction Regarding Roadside Assessments for Use in
Prosecutions for Operating Under the Influence of Marijuana
You heard testimony in this case that the defendant, at the
request of a police officer, performed or attempted to perform
various roadside assessments, such as [Here outline the nature
of the evidence, e.g., walking a straight line, balancing on one
foot]. These roadside assessments are not scientific tests of
impairment by marijuana use. A person may have difficulty
performing these tasks for many reasons unrelated to the
consumption of marijuana.
It is for you to decide if the defendant's performance on
these roadside assessments indicate that his [her] ability to
operate a motor vehicle safely was impaired. You may consider
this evidence solely as it relates to the defendant's balance,
coordination, mental clarity, ability to retain and follow
directions, ability to perform tasks requiring divided
attention, and other skills you may find are relevant to the
safe operation of a motor vehicle.
It is for you to determine how much, if any, weight to give
the roadside assessments. In making your determination, you may
consider what the officer asked the defendant to do, the
circumstances under which they were given and performed, and all
of the other evidence in this case.
Finally, evidence of how a defendant performed in roadside
assessments, standing alone, is never enough to convict a
defendant of operating under the influence of marijuana.