Case Title: Commonwealth v. Dunphe

Citation: 

Docket Number: SJC-12533

State: massachusetts

Court: Massachusetts Supreme Court

Date: 2020-10-07T00:00:00Z

Document:
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SJC-12533 
 
COMMONWEALTH  vs.  ALDO W. DUNPHE. 
 
 
 
Worcester.     December 10, 2019. - October 7, 2020. 
 
Present:  Gants, C.J., Gaziano, Lowy, Budd, & Cypher, JJ.1 
 
 
Homicide.  Criminal Responsibility.  Insanity.  Mental 
Impairment.  Practice, Criminal, Instructions to jury, 
Capital case. 
 
 
 
Indictments found and returned in the Superior Court 
Department on March 18, 2014. 
 
 
The cases were tried before James R. Lemire, J., and a 
motion for a new trial, filed on May 31, 2018, was heard by 
Anthony M. Campo, J. 
 
 
 
Leslie W. O'Brien for the defendant. 
 
Susan M. Oftring, Assistant District Attorney, for the 
Commonwealth. 
 
 
GANTS, C.J.  On November 5, 2013, four days after he was 
voluntarily admitted to the psychiatric ward of the University 
of Massachusetts Memorial Medical Center (medical center), the 
                     
 
1 Chief Justice Gants participated in the deliberation on 
these cases and authored this opinion prior to his death. 
2 
 
 
defendant physically attacked and killed Ratna Bhattarai, 
another patient there.  The sole issue at trial was whether the 
Commonwealth had proved beyond a reasonable doubt that the 
defendant was criminally responsible for the killing. 
There was no dispute that the defendant had smoked cannabis 
almost daily, often in large amounts, for approximately six or 
seven years before he was admitted to the psychiatric ward and 
that he had not smoked cannabis after he was admitted.  Nor was 
there any dispute that, at the time of the killing, the 
defendant suffered from hallucinations and believed, with no 
rational basis, that the victim was his biological father, who 
had abused the defendant as a child. 
The Commonwealth's expert testified that, at the time of 
the killing, the defendant suffered from a "substance-induced 
psychotic disorder and a cannabis withdrawal condition" that 
resulted in hallucinations; the expert further testified that 
the defendant did not have a mental disease or defect.  The 
defense expert testified that the defendant's delusions at the 
time of the killing were consistent with a diagnosis of 
schizophrenia, which he characterized as a mental disease or 
defect.  He noted that some of the symptoms of cannabis 
withdrawal may have played a role in the killing and that it was 
"a bit of a challenge" to assess because some of the symptoms of 
cannabis withdrawal are the same as schizophrenia.  But he 
3 
 
 
declared that delusions and hallucinations are not part of 
cannabis withdrawal disorder and that the defendant's marijuana 
use, by itself, could not explain his conduct on the day of the 
killing. 
A Superior Court jury, after having been provided by the 
judge with legal instructions regarding criminal responsibility 
that closely tracked those in our Model Jury Instructions on 
Homicide (2018)2, found the defendant guilty of murder in the 
first degree on the theory of extreme atrocity or cruelty.3  We 
conclude that that there is a substantial likelihood of a 
miscarriage of justice arising from the application of our model 
jury instructions regarding criminal responsibility to the 
peculiar facts in these cases.  We therefore vacate the 
convictions and remand the cases for a new trial.  We also 
provisionally revise our model jury instructions regarding 
                     
2 The trial in these cases took place in 2016, when the 2013 
version of our Model Jury Instructions on Homicide was in 
effect.  In 2018, we significantly revised these instructions.  
However, because there were no substantive changes in our 
instructions regarding criminal responsibility, we refer to the 
current version of the Model Jury Instructions on Homicide 
throughout this opinion. 
 
3 The jury also convicted the defendant of assault and 
battery, causing serious bodily injury, in violation of G. L. 
c. 265, § 13A (b), and assault and battery by means of a 
dangerous weapon, in violation of G. L. c. 265, § 15A (b). 
4 
 
 
criminal responsibility to address what we conclude is a 
potential and problematic risk of confusion.4 
Background.  1.  Evidence at trial.  We summarize the facts 
that the jury could have found at trial, reserving certain 
details for our discussion of the legal issues.  See 
Commonwealth v. Waweru, 480 Mass. 173, 174 (2018). 
a.  Events leading to the defendant's admission to the 
psychiatric ward.  When the defendant was eight years old, he 
and his younger sister were adopted.  His adoptive mother 
testified that, although he had been a good student, he had 
difficulty adjusting to college and began experimenting with 
cannabis during his freshman year. 
In 2008, after having dropped out of college, the defendant 
began dating a woman he later married.  The defendant's wife 
testified that in the first couple of years of their 
relationship, the defendant used cannabis "occasionally," once 
or twice a month, but in 2010, he began to smoke more 
frequently.  Although he sometimes stopped using cannabis for 
                     
4 We leave the final revisions to be crafted by the Standing 
Committee on the Model Jury Instructions on Homicide.  See, 
e.g., Commonwealth v. Gomes, 470 Mass. 352, 376 (2015), S.C., 
478 Mass. 1025 (2018) (proposing jury instruction regarding 
eyewitness identification but making it "provisional to allow 
for public comment and possible future revision before 
[declaring] it a model"). 
5 
 
 
weeks at a time, there were other periods when he smoked on a 
daily basis.  She never saw him suffer from withdrawal symptoms. 
The couple dated for five years before getting married on 
October 13, 2013.  It was in the months leading up to their 
wedding that the defendant's wife began to notice changes in the 
defendant's personality and behavior.  In February 2013, the 
defendant accused her of giving his mother "dirty looks."  He 
also accused his wife of having been unfaithful, both before 
their wedding and during their honeymoon.  He made a number of 
additional unsubstantiated accusations during that period, such 
as that she had told her father that the defendant had beaten 
their cat and that her mother had wanted the family dog to be 
killed.  During their honeymoon, the defendant also expressed 
concern that his wife was being followed. 
When the couple returned to Massachusetts after their 
honeymoon, the defendant continued to accuse his wife of 
infidelity and called her "psychotic."  She found it 
increasingly difficult to have conversations with the defendant 
because he would skip between topics without finishing his train 
of thought.  He also began staring into space and smiling at 
inappropriate times, and his laugh changed.  The defendant's 
wife said that the defendant began to complain that he was 
having bad dreams and difficulty sleeping. 
6 
 
 
On October 31, 2013, the defendant's wife received a 
telephone call from the defendant saying he was "going to rehab" 
and would not be home for a few weeks.  Later that night, he 
came home and told her that he had been followed by members of a 
biker gang called the Vigilantes and that he had considered 
killing himself by overdosing on sleeping pills.  He also told 
her that he wanted to break up with her and behaved 
"aggressive[ly]" toward her, which he had never done before.  He 
eventually left and went to his parents' house. 
b.  The killing.  The next day, on November 1, 2013, the 
defendant was voluntarily admitted to the psychiatric ward.  
Doctors diagnosed him with "Psychosis Not-Otherwise-Specified" 
because they could not determine whether his psychosis 
originated from his recent cannabis use or from a preexisting 
mental disease.  The defendant's wife and his adoptive parents 
went to visit him on November 2, and he told them that he had 
seen his biological father in the psychiatric ward.  On the 
evening of November 4, he spoke about the victim to a nurse, 
telling her:  "The little guy is my father.  He's been in a time 
travel.  He's been gone for 2,500 years. I'll do that, too, but 
I can do it in ten."  In reality, the defendant's biological 
father lived in Guatemala and had abused the defendant as a 
young child. 
7 
 
 
On November 5, the defendant suffocated the victim with a 
pillow, punched him repeatedly in the face, smashed his head 
against the cement floor, and finally stuffed cloth into the 
victim's nose and mouth.  The defendant then washed his hands, 
gathered his clothes, and went back to his room. 
A medical center police officer arrived shortly after the 
killing and spoke with the defendant.  The defendant was lying 
in bed, with blood on his socks and on his pants legs.  The 
officer recited the Miranda warnings, and the defendant said 
that he understood them.  The officer asked him what had 
happened, and the defendant said that the victim, whose name he 
did not know, had threatened to kill him earlier in the day.  He 
said he waited for the nurse to leave the victim's room after 
she had brought him lunch, then entered the room, grabbed the 
victim by the neck, and dragged him to the ground.  He then 
began to punch the victim, and later stuffed towels in his mouth 
and in his nostrils.  He said he did not mean to kill the 
victim; he just wanted to beat him up. 
Later that day, two State police troopers arrived to 
interview the defendant.  They again gave him Miranda warnings, 
which he again said he understood.  The defendant admitted to 
killing the victim, stating that he did so because the victim 
was his father who had threatened to kill him and was keeping 
him in the psychiatric ward against his will. 
8 
 
 
The victim died several days later due to injuries 
resulting from the defendant's attack. 
c.  Expert testimony.  At trial, the defendant did not deny 
killing the victim but claimed that he lacked criminal 
responsibility "because, due to a mental disease or defect, he 
lacked the substantial capacity at that time . . . to appreciate 
the wrongfulness of his conduct [or] to conform his conduct to 
the requirements of the law."  Commonwealth v. DiPadova, 460 
Mass. 424, 428 (2011), citing Commonwealth v. McHoul, 352 Mass. 
544, 546-547 (1967). 
The defendant's expert, Dr. John Daignault, testified that, 
at the time of the killing, the defendant "was in the throes of 
an acute psychotic episode with a diagnosis of schizophrenia, 
and he perceived the victim as an imminent threat to him; and he 
believed, in his delusional state, that he was protecting his 
own life from the threat that [the victim], he believed, posed 
to him."  He noted that the defendant's hallucinations, 
delusions, and grossly disorganized behavior -- such as 
believing that a biker gang wanted to kill him and hearing a 
radio station in his head that relayed imaginary information 
about his wife committing adultery -- were consistent with a 
diagnosis of paranoid schizophrenia around the time of the 
attack.  He further cited the defendant's behavior immediately 
following the crime, such as calmly, coherently, and 
9 
 
 
cooperatively admitting to the crime to the police while 
maintaining his strong belief that the victim was his biological 
father who had come to harm the defendant at the psychiatric 
ward.  The defendant, Daignault reasoned, did not try to hide 
his culpability or the evidence of his guilt, nor did he express 
any anxiety for his actions, because he was "floridly psychotic" 
and not "malingering" at the time of the attack. 
Daignault opined that the defendant had a mental disease or 
defect at the time of the killing:  schizophrenia.  He also 
testified that he believed the defendant lacked the substantial 
capacity to appreciate the wrongfulness of his conduct and that 
the schizophrenia had "stripped [the defendant] of his ability 
to conform his behavior to the requirements of the law."  
Daignault therefore concluded that the defendant lacked criminal 
responsibility. 
As to the defendant's cannabis habit, Daignault testified 
that the defendant's psychosis on the day of the crime resulted 
from schizophrenia and not from any withdrawal symptoms due to 
the defendant's cannabis dependency.  He noted that some experts 
believe that cannabis consumption can trigger schizophrenia and 
that such consumption may have contributed to the defendant's 
psychosis; cannabis withdrawal, however, is not associated with 
delusions and hallucinations.  Daignault therefore concluded 
that while the defendant might have suffered from cannabis 
10 
 
 
withdrawal syndrome -- which can lead to sleeplessness and 
aggression -- at the time of the attack, such withdrawal alone 
could not account for the defendant's serious delusions and 
hallucinations, which fell far outside the syndrome's normal 
presentation. 
In contrast, the Commonwealth's expert, Dr. Fabian Saleh, 
opined that, at the time of the killing, the defendant did not 
suffer from schizophrenia or another delusional disorder, but 
rather had a "substance-induced psychotic disorder and a 
cannabis withdrawal condition," which, he stated, did not 
qualify as a mental disease or defect.  In short, he testified 
that the killing was "clearly cannabis induced . . . in the 
context of withdrawal." 
Saleh testified that the defendant met all of the criteria 
for cannabis withdrawal:  (1) use of cannabis on a daily or 
almost daily basis, and (2) presence of all of the relevant 
symptoms, such as anger or aggressiveness, restlessness, sleep 
disturbance, anxiety, change in mood, depression, and "bodily 
symptoms."  He also noted that cannabis withdrawal peaks within 
seven days, with signs of withdrawal twenty-four to seventy-two 
hours after the abrupt cessation of the cannabis.  Here, "on day 
five, he is engaging in this act of aggression." 
Saleh further testified that the defendant did not meet the 
criteria for a diagnosis of schizophrenia under the Diagnostic 
11 
 
 
and Statistical Manual of Mental Disorders, Fifth Edition.  He 
noted that to diagnose a patient with schizophrenia, "you have 
to rule out a substance-induced or medical-induced presentation 
that could account for what's going on here."  And contrary to 
Daignault's view about the symptoms of cannabis withdrawal, 
Saleh suggested that cannabis withdrawal syndrome can cause 
delusions and hallucinations and that the defendant's symptoms 
more closely tracked cannabis withdrawal than schizophrenia.  In 
particular, he explained that the defendant acted violently only 
on one day, the day of the crime, a pattern consistent with the 
timeline of cannabis withdrawal but not schizophrenia. 
Saleh also testified that the defendant's heavy use of 
cannabis since the age of eighteen had damaged his brain.  And 
he noted that the defendant recognized that his cannabis use 
"definitely" changed his brain chemistry, citing what the 
defendant had told the state troopers after the killing:  that 
he heard voices when he was high on cannabis, and that, whenever 
he smoked, it "set[] off other drugs" that he had done before, 
including "acid, mushrooms, cocaine," and prescription pills of 
Percocet and Clonopin. 
Saleh opined that the defendant "[c]learly understood that 
killing somebody was against the law" and that he "[a]bsolutely" 
had the capacity to conform his conduct to the law.  He based 
this determination on his observations that the defendant's 
12 
 
 
"behaviors were organized, goal-directed, planned, [and] 
thoughtful," in that he "had an objective in mind"; he "took the 
proper steps to get into the victim's room, closed the room, 
confronted the victim, assaulted the victim, ultimately ended up 
killing the victim, took a shower, then left the room."  "[A]ll 
of this," he concluded, "suggests that despite the fact that he 
misperceived the victim as being his father, he knew . . . of 
the wrongfulness of his conduct and was able to conform his 
conduct to the requirement of the law." 
2.  Motion for a new trial.  The defendant filed a motion 
for a new trial under Mass. R. Crim. P. 30 (b), as appearing in 
435 Mass. 1501 (2001), or to reduce the verdict, under Mass. R. 
Crim. P. 25 (b), as amended, 420 Mass. 1502 (1995), which the 
motion judge (who was not the trial judge) denied.  With respect 
to the motion for a new trial, the defendant argued that he was 
deprived of his constitutional right to the effective assistance 
of counsel because his trial counsel failed to object to the 
judge's instructions regarding the relationship between 
voluntary intoxication and criminal responsibility, where there 
was no evidence that the defendant was voluntarily intoxicated 
at the time of the killing.  The motion judge disagreed, 
declaring that "[o]ur case law interprets voluntary intoxication 
broadly, suggesting that it can arise subject to a defendant's 
drug and alcohol addiction."  The judge added that "[t]o 
13 
 
 
construe voluntary intoxication to be so limited so as to be 
restricted only to immediate or contemporaneous ingestion or 
inhalation would ignore the science regarding the short and 
long-term effects of chemical use and misuse on the human body." 
With respect to the motion to reduce the verdict, the 
defendant argued that a verdict of murder in the second degree 
was more consonant with justice, because there was strong 
evidence that mental illness was the driving force in the 
killing in these cases.  The judge disagreed, concluding that 
the weight of the evidence supported the finding of murder in 
the first degree on the theory of extreme atrocity or cruelty 
"in light of the brutality of the defendant's acts towards the 
victim." 
The defendant appeals both from his conviction and from the 
denial of his motion for a new trial. 
Discussion.  The defendant claims that (1) the evidence was 
insufficient as a matter of law to permit a rational juror to 
find beyond a reasonable doubt that the defendant was criminally 
responsible; (2) in the circumstances of these cases, the 
judge's instruction to the jury on criminal responsibility 
created a substantial likelihood of a miscarriage of justice; 
(3) the judge erred in allowed Saleh to testify about the 
defendant's prior drug dealing in support of his opinion that 
the defendant did not suffer from schizophrenia; and (4) the 
14 
 
 
judge erred in instructing the jury that, in considering the 
question of criminal responsibility, they may consider that "a 
great majority of persons are sane and the probability that any 
particular person is sane."  Before we address these four 
claims, we first summarize our law regarding the defense of lack 
of criminal responsibility, focusing on the intersection between 
criminal responsibility and voluntary intoxication. 
1.  Defense of lack of criminal responsibility.  Where a 
defendant offers a defense of lack of criminal responsibility, 
the burden rests on the Commonwealth to "prove beyond a 
reasonable doubt that the defendant was criminally responsible 
at the time the alleged crime was committed."  Model Jury 
Instructions on Homicide 1.  See Commonwealth v. Berry, 457 
Mass. 602, 612 (2010), S.C., 466 Mass. 763 (2014), citing 
McHoul, 352 Mass. at 546-547.  Our Model Jury Instructions on 
Homicide declare that "[a] person is not criminally responsible 
for his conduct if he has a mental disease or defect, and, as a 
result of that mental disease or defect, lacks substantial 
capacity either to appreciate the criminality or wrongfulness of 
his conduct or to conform his conduct to the requirements of the 
law."  Model Jury Instructions on Homicide 2.  See McHoul, supra 
(lack of criminal responsibility defense). 
a.  Mental disease or defect.  If the Commonwealth proves 
beyond a reasonable doubt that the defendant did not have a 
15 
 
 
mental disease or defect at the time of the crime, the defense 
of lack of criminal responsibility fails.  Even if the jury were 
to conclude that the defendant lacked substantial capacity, the 
defendant must be found criminally responsible if the lack of 
substantial capacity did not result from a mental disease or 
defect but derived solely from another source, such as voluntary 
intoxication. 
Our model jury instructions do not define the term "mental 
disease or defect."  Only two bits of guidance are given to 
jurors:  (1) it "is a legal term, not a medical term; it need 
not fit into a formal medical diagnosis," and (2) 
"[i]ntoxication caused by the voluntary consumption of alcohol 
or drugs, by itself, is not a mental disease or defect."  Model 
Jury Instructions on Homicide 3, 5.  The absence of further 
guidance in our model jury instructions "arises not because the 
term 'mental disease or defect' is so clear on its face that 
such an explanation would be superfluous.  The reason may well 
be the opposite; the subject is so complex and obscure that any 
general explanatory formula is likely to mislead and confuse."  
Commonwealth v. Fuller, 421 Mass. 400, 411 (1995).  See 
Commonwealth v. Sliech-Brodeur, 457 Mass. 300, 328 (2010) ("a 
judge is not required to define 'mental disease or defect' but 
has discretion to provide the instructions that are appropriate 
to the context"). 
16 
 
 
Although our model jury instructions are spare, it should 
be clear that a person without a mental disease or defect who 
gets drunk or high and then robs a convenience store is not 
entitled to a criminal responsibility defense even if he or she 
was so intoxicated as to lack substantial capacity.  See Berry, 
457 Mass. at 617, citing Commonwealth v. Sheehan, 376 Mass. 765, 
770 (1978) ("A defendant's lack of criminal responsibility 
cannot be solely the product of intoxication caused by her 
voluntary consumption of alcohol or another drug").  See also J. 
Dressler, Understanding Criminal Law § 24.05[A] (8th ed. 2018) 
(noting that common law does not recognize defense of "temporary 
insanity" resulting from "voluntary ingestion of drugs or 
alcohol").  Nor is a person without a mental disease or defect 
entitled to a criminal responsibility defense if he or she robs 
that convenience store in the throes of opioid withdrawal, 
desperate for the money to purchase the drugs needed to end the 
pangs of withdrawal.  Intoxication from alcohol or the high from 
drugs is not a mental disease or defect where the loss of 
capacity ends when the effects of the alcohol or drug wear off; 
a mental disease or defect is something more enduring, 
reflecting something about the person's brain chemistry that, 
although perhaps not permanent, is more than the transient 
effect of the person's substance use.  See id. at § 24.05[B] 
("The law distinguishes between mental impairment that does not 
17 
 
 
extend beyond the period of voluntary intoxication ['temporary 
insanity'], for which no defense is available, and insanity 
resulting from long-term use of drugs or alcohol.  If the 
unsoundness of mind, although produced by long-term alcohol or 
drug abuse, has become 'fixed' or 'settled,' the general, but 
not universal, rule is that the defendant may assert a 
traditional insanity defense").5 
What our case law declares, but our model jury instructions 
do not, is that if a defendant has a mental disease or defect, 
                     
5 A number of our sister States recognize a "settled 
insanity" defense.  See, e.g., People v. Travers, 88 Cal. 233, 
239-240 (1891) ("settled insanity produced by a long-continued 
intoxication affects responsibility in the same way as insanity 
produced by any other cause.  But it must be 'settled insanity,' 
and not merely a temporary mental condition produced by recent 
use of intoxicating liquor"); Bieber v. People, 856 P.2d 811, 
815 (Colo. 1993), cert. denied, 510 U.S. 1054 (1994) ("The 
doctrine of 'settled insanity' draws a distinction between 
voluntary intoxication, universally recognized as not 
constituting a defense, and 'insanity' arising from the long-
term use of intoxicants but separate from immediate 
intoxication"); People v. Free, 94 Ill. 2d 378, 408, cert. 
denied, 464 U.S. 865 (1983) ("A voluntary intoxication or a 
voluntary drugged condition precludes the use of the insanity 
defense unless the mental disease or defect is traceable to the 
habitual or chronic use of drugs or alcohol . . . and such use 
results in a 'settled' or 'fixed' permanent type of insanity" 
[citations omitted]); White v. Commonwealth, 272 Va. 619, 626 
(2006) ("a mental disease or defect caused by chronic abuse of 
alcohol or drugs will support the defense of insanity . . . We 
have also commonly referred to this permanent condition as 
'settled insanity'" [citations omitted]). 
 
Although we have never used the language of "settled 
insanity," our guidance in Commonwealth v. Herd, 413 Mass. 834, 
840-841 (1992), discussed infra, is substantively similar. 
18 
 
 
its origins are irrelevant:  it does not matter whether the 
disease or defect arose from genetics, from a childhood disease 
or accident, from lead poisoning, from the use of prescription 
medication, or from the chronic use of alcohol or illegal drugs.  
See Commonwealth v. Herd, 413 Mass. 834, 840-841 (1992).  A 
drug-induced mental disease or defect still constitutes a mental 
disease or defect for purposes of a criminal responsibility 
defense.  Id.  In reaching that conclusion in Herd, we declared: 
"The weight of authority in this country recognizes an 
insanity defense that is based on a mental disease or 
defect produced by long-term substance abuse.  We see no 
logical reason for rejecting a drug-induced mental disease 
or defect as a basis for the application of the McHoul test 
simply because the disease or defect is caused only by the 
drug ingestion.  We are unwilling, in order to justify a 
homicide conviction, to permit the moral fault inherent in 
the unlawful consumption of drugs to substitute for the 
moral fault that is absent in one who lacks criminal 
responsibility" (footnote omitted). 
 
Id.  Therefore, if the defendant suffered from schizophrenia or 
a similar psychotic disorder at the time of the killing, he had 
a mental disease or defect regardless of its cause or the 
defendant's understanding of its cause. 
b.  Interaction between a mental disease or defect and the 
voluntary use of alcohol or drugs.  Our model jury instructions 
become even more challenging where the defendant both has a 
mental disease or defect and was under the influence of drugs or 
alcohol at the time of the crime.  Our instructions essentially 
19 
 
 
describe three different scenarios, each with different legal 
consequences. 
Under the first scenario, the defendant, at the time the 
crime was committed, had a mental disease or defect that by 
itself caused him to lack the required substantial capacity.  
Where this is true, the defendant is not criminally responsible 
even if the defendant was also under the influence of drugs or 
alcohol and his consumption of these substances made the 
symptoms of his mental disease or defect worse.  Indeed, where 
this is true, the defendant is not criminally responsible even 
if the defendant knew that consuming drugs or alcohol would make 
his symptoms worse.  See Model Jury Instructions on Homicide 7. 
Under the second scenario, the defendant's mental disease 
or defect did not, by itself, cause the defendant to lack 
substantial capacity; however, his consumption of drugs or 
alcohol triggered or intensified his preexisting mental disease 
or defect, causing the defendant to lose substantial capacity.  
See DiPadova, 460 Mass. at 432 ("a defendant's mental disease or 
defect may interact with . . . drugs in such a way as to push 
the defendant 'over the edge' from" having substantial capacity 
into lacking substantial capacity).  Where this is true, and 
where the defendant did not know or have reason to know that his 
consumption of drugs would trigger or intensify his mental 
20 
 
 
disease or defect, the defendant is also not criminally 
responsible.  See Model Jury Instructions on Homicide 5-6. 
The third scenario is a variation on the second, the 
difference being that the Commonwealth proves beyond a 
reasonable doubt that the defendant knew or had reason to know 
that his consumption of drugs or alcohol would trigger or 
intensify a mental disease or defect that could cause the 
defendant to lose substantial capacity.  Where this is true, the 
defendant "is criminally responsible for his resulting conduct" 
(emphasis in original).  Model Jury Instructions on Homicide 6-
7, citing DiPadova, 460 Mass. at 439-440.  In effect, if a 
defendant's mental disease or defect alone did not cause the 
loss of substantial capacity, and the defendant knew or had 
reason to know that his consumption of drugs or alcohol would 
cause him to lose substantial capacity, our law regards it as if 
the loss of substantial capacity arose solely from voluntary 
intoxication.  See Model Jury Instructions on Homicide 5 ("Where 
a defendant lacked substantial capacity to appreciate the 
criminality or wrongfulness of his conduct or to conform his 
conduct to the law solely as a result of voluntary intoxication, 
then he is criminally responsible for his conduct"). 
But it is important to understand what this third scenario 
does not mean.  It does not mean that if the defendant knew or 
had reason to know that chronic consumption of alcohol or drugs 
21 
 
 
might eventually affect his brain chemistry so as to cause a 
mental disease or defect, he cannot claim lack of criminal 
responsibility if he loses substantial capacity as a result of 
that mental disease or defect.  See Herd, 413 Mass. at 843. 
So, if a person with alcohol abuse disorder knows or has 
reason to know that his or her chronic use of alcohol could 
eventually result in an organic brain syndrome, that person is 
not barred from claiming a lack of criminal responsibility if he 
or she committed a crime after losing substantial capacity as a 
result of an organic brain syndrome.  Id. at 839-840 ("a mental 
disease caused by drug abuse, even if temporary in nature, may 
nevertheless [permit a lack of criminal responsibility defense] 
if the condition was not limited to periods of the defendant's 
intoxication").  Cf. Commonwealth v. Rosario, 477 Mass. 69, 73-
74 (2017) (discussing delirium tremens).  We regard organic 
brain syndromes as a mental disease or defect even if it were 
the foreseeable result of chronic alcohol abuse.  See 
Commonwealth v. Brennan, 399 Mass. 358, 362-363 (1987) (judge in 
murder trial erred by not allowing expert testimony that organic 
brain syndrome resulting from alcoholism could form basis of 
lack of criminal responsibility defense).  Similarly, if a 
person with a substance use disorder knows or should know that 
chronic use of cannabis increases the risk of schizophrenia, the 
person is not barred from claiming a lack of criminal 
22 
 
 
responsibility if the person committed a crime after losing 
substantial capacity as a result of schizophrenia.  We regard 
schizophrenia as a mental disease or defect even where it is the 
foreseeable result of chronic drug use.6 
Implicit in our instructions is that where a person 
voluntarily chooses to become intoxicated from alcohol or high 
from drugs, that person is responsible for the decision to get 
drunk or high and therefore is criminally responsible for his or 
her subsequent conduct; that is why it is characterized as 
voluntary intoxication.  Similarly implicit in our model jury 
instruction regarding the third scenario,  is that where a 
person knows or has reason to know that his or her use of 
alcohol or drugs will interact with his or her mental disease or 
defect and push the person over a psychological "edge" into a 
loss of substantial capacity, that person is responsible for the 
decision to use drugs or alcohol in these circumstances and 
therefore criminally responsible for his or her subsequent 
conduct. 
                     
6 It is worth noting that while increasing evidence points 
to a correlation between cannabis use and schizophrenia, a 
causal relationship between cannabis exposure and the 
development of schizophrenia remains highly controversial even 
within the scientific community.  See, e.g., Wilkenson,  
Radhakrishnan, & D'Souza, Impact of Cannabis Use on the 
Development of Psychotic Disorders, 1 Current Addiction Reports 
115, 117 (2014). 
23 
 
 
With this background, we now address the claims of error 
raised by the defendant. 
2.  Sufficiency of the evidence.  The defendant claims 
that, even if we view the evidence in the light most favorable 
to the Commonwealth, as we must, no rational trier of fact could 
conclude that the Commonwealth had met its burden of proving 
beyond a reasonable doubt that the defendant is criminally 
responsible.  See Commonwealth v. Lawson, 475 Mass. 806, 811-812 
(2016).  We have said that "[i]t will be a rare case where the 
totality of the evidence regarding the defendant's conduct and 
the circumstances of the offense will not be sufficient to 
defeat a defendant's motion for a required finding of not guilty 
by reason of lack of criminal responsibility."  Id. at 817.  
These cases are not examples of that rare case. 
A reasonable jury could have credited Saleh's expert 
opinion that the defendant did not have a mental disease or 
defect but instead suffered from delusions and hallucinations 
solely because of his withdrawal from cannabis.  A reasonable 
jury also could have credited Saleh's opinion that the defendant 
could "appreciate the wrongfulness of his conduct and . . . 
conform his conduct to the requirement of the law" at the time 
of the crime because "[h]is behaviors were organized, goal-
directed, planned, thoughtful."  The defendant is therefore not 
24 
 
 
entitled to a judgment of acquittal as a matter of law based on 
the insufficiency of the evidence of criminal responsibility. 
3.  Jury instruction on defense of lack of criminal 
responsibility.  The defendant claims that, in the unusual 
circumstances of these cases, the judge's jury instructions 
regarding criminal responsibility created a substantial 
likelihood of a miscarriage of justice.  Because the judge's 
instructions were essentially our model jury instructions, we 
must consider whether our own instructions, applied in the 
context of these cases, created a substantial risk of juror 
confusion regarding the law of criminal responsibility.  We 
conclude that they did.  The danger arose not from what the 
instructions said regarding mental disease or defect and the 
interaction with the voluntary consumption of alcohol or drugs, 
but from what they failed to say. 
The model jury instructions provide: 
"The phrase 'mental disease or defect' is a legal term, not 
a medical term; it need not fit into a formal medical 
diagnosis.  The phrase "mental disease or defect" does not 
include an abnormality characterized only by repeated 
criminal conduct.  It is for you to determine in light of 
all the evidence whether the defendant had a mental disease 
or defect.  If the Commonwealth has proved to you beyond a 
reasonable doubt that the defendant was not suffering from 
a mental disease or defect at the time of the killing, the 
Commonwealth has satisfied its burden of proving that the 
defendant was criminally responsible." 
 
Model Jury Instructions on Homicide 3.  As discussed earlier, 
this instruction is spare, but, in the absence of evidence of 
25 
 
 
alcohol or drug consumption, it does not pose a significant risk 
of confusion, especially where there is likely to be expert 
testimony on this subject.  But where there is evidence that a 
defendant had a mental disease or defect and consumed drugs or 
alcohol at or about the time of the offense, our model jury 
instructions create two potential risks of juror confusion in 
the circumstances of these cases. 
a.  Underlying cause or origin of mental disease or defect 
instruction.  Our model jury instructions provide: 
"A defendant's lack of criminal responsibility must be due 
to a mental disease or defect.  Intoxication caused by the 
voluntary consumption of alcohol or drugs, by itself, is 
not a mental disease or defect.  Where a defendant lacked 
substantial capacity to appreciate the criminality or 
wrongfulness of his conduct or to conform his conduct to 
the law solely as a result of voluntary intoxication, then 
he is criminally responsible for his conduct." 
 
Model Jury Instructions on Homicide 5. 
After hearing the expert testimony and the prosecutor's 
closing argument in these cases, a reasonable jury might have 
understood this instruction to mean that if the defendant's 
chronic use of cannabis had caused his mental disease or defect, 
then the law would not recognize him to have a mental disease or 
defect.  This risk was magnified by Saleh's opinion that, at the 
time of the killing, the defendant had experienced a temporary 
episode of "drug-induced psychosis," as opposed to a more 
prolonged or permanent psychotic disorder, and that this episode 
26 
 
 
did not amount to a mental disease or defect.  Where it was 
apparent that the defendant had no access to cannabis for at 
least four days before the killing and that he was therefore not 
high at the time of the killing, the jury might have understood 
Saleh's testimony to mean that a mental disease or defect 
induced by drugs was not, under the law, a mental disease or 
defect. 
The potential for misunderstanding was further intensified 
by the prosecutor's closing argument, where, in asking the jury 
to compare Saleh's expert testimony with Daignault's, he asked 
the rhetorical question, "Did Dr. Daignault . . . possess the 
medical training to understand the biological aspects of 
marijuana, as Dr. Saleh explained to you about the blood/brain 
barrier, about the long-term effects of smoking marijuana on a 
daily basis and how that affects the brain."  The inference the 
prosecutor invited was that, if the defendant's long-term use of 
cannabis affected his brain and even caused his schizophrenia, 
he was criminally responsible.  But as explained above, allowing 
the jury to make this inference would be incorrect:  a lack of 
criminal responsibility defense is not foreclosed where the 
defendant's long-term drug use caused his mental disease or 
defect. 
This risk of confusion could be diminished by adding the 
highlighted sentences to the model jury instruction: 
27 
 
 
"A defendant's lack of criminal responsibility must be due 
to a mental disease or defect.  You need not consider the 
cause or origin of a mental disease or defect.  All that 
you need to determine as to this issue is whether the 
Commonwealth has proved beyond a reasonable doubt that the 
defendant did not have a mental disease or defect at the 
time of the alleged offense.  Intoxication caused by the 
voluntary consumption of alcohol or drugs, by itself, is 
not a mental disease or defect.  But a mental disease or 
defect might be caused by or result from a defendant's 
earlier chronic use of alcohol or drugs.  Where a defendant 
lacked substantial capacity to appreciate the criminality 
or wrongfulness of his conduct or to conform his conduct to 
the law solely as a result of voluntary intoxication, and 
not from a mental disease or defect, then he is criminally 
responsible for his conduct." 
 
b.  "Knew or had reason to know" instruction.  Our model 
jury instructions address what we have described as the third 
scenario, where there is evidence that the defendant knew or 
should have known that his consumption of drugs or alcohol would 
trigger or intensify a preexisting mental disease or defect and 
thereby cause a loss of substantial capacity, with the following 
instruction: 
"A defendant who lost the substantial capacity I have just 
described after he consumed drugs or alcohol, and who knew 
or had reason to know that his consumption would trigger or 
intensify in him a mental disease or defect that could 
cause him to lack that capacity, is criminally responsible 
for his resulting conduct.  In deciding whether the 
defendant had reason to know about the consequences of his 
consumption of drugs or alcohol, you should consider the 
question solely from the defendant's point of view, 
including his mental capacity and his past experience with 
drugs or alcohol.  But you must keep in mind that where a 
defendant, at the time the crime is committed, had a mental 
disease or defect that by itself caused him to lack the 
required substantial capacity, he is not criminally 
responsible for his conduct regardless of whether he used 
or did not use alcohol or drugs.  That is true even if he 
28 
 
 
did use alcohol or drugs and the alcohol or drug use made 
the symptoms of his mental disease or defect worse, and 
even if he knew they would make his symptoms worse"). 
 
Model Jury Instructions on Homicide 6-7. 
 
This instruction does not apply under the facts of these 
cases.  To be sure, there was evidence that the defendant knew 
that he hallucinated when he was high on cannabis, but where he 
had not had access to cannabis for four days, there was no 
evidence that he was high at the time of the killing.  Nor did 
the Commonwealth present any evidence that the defendant knew or 
should have known that he could lose substantial capacity as a 
result of his withdrawal from cannabis. 
In closing argument, however, the prosecutor suggested that 
the defendant could be found criminally responsible under this 
third scenario if the jury found that he knew that his prior 
chronic cannabis use made him paranoid and delusional.  The 
prosecutor argued: 
"The defendant had some problems, but it doesn't absolve 
him of his responsibility for deliberately killing another 
person.  And these problems he brought upon himself from 
his daily use of marijuana.  The defendant had a drug 
problem . . . that he knew made him paranoid and 
delusional.  His withdrawal made him a killer." 
 
Later in his argument, the prosecutor declared: 
"The defendant knew that smoking marijuana daily was bad 
for him.  He learned it in school.  He learned it from his 
parents.  Yet, still, he smoked it every day.  And what did 
he say to the police?  'Whenever I smoke pot, it sort of 
sets off other drugs that I have done before." 
 
29 
 
 
A jury who credited Daignault's opinion that the defendant 
had the mental disease or defect of schizophrenia at the time of 
the killing could have understood from the prosecutor's argument 
and this instruction that the defendant was still criminally 
responsible if he knew that his prior use of cannabis over the 
years made his schizophrenia more severe.  But just as our case 
law does not care what caused a defendant's mental disease or 
defect, it also does not care what may have, over the course of 
time, intensified or worsened that mental disease or defect.  
This instruction does not focus on a defendant's past drug or 
alcohol use, but only on his or her present use and the 
intoxicating effects from that present use. 
The risk of confusion on this point could be diminished if 
we amended our model jury instruction as follows, with the 
underlined revisions: 
"A defendant who lost the substantial capacity I have just 
described when voluntarily intoxicated by drugs or alcohol, 
and who knew or had reason to know that his intoxication 
would trigger or intensify in him a mental disease or 
defect that could cause him to lack that capacity, is 
criminally responsible for his resulting conduct.  In 
deciding whether the defendant had reason to know about the 
consequences of his voluntary intoxication from drugs or 
alcohol, you should consider the question solely from the 
defendant's point of view, including his mental capacity 
and his past experience with drugs or alcohol.  But you 
must keep in mind that where a defendant, at the time the 
crime is committed, had a mental disease or defect that by 
itself caused him to lack the required substantial 
capacity, he is not criminally responsible for his conduct 
regardless of whether he used or did not use alcohol or 
drugs.  That is true even if he did use alcohol or drugs 
30 
 
 
and the alcohol or drug use made the symptoms of his mental 
disease or defect worse, and even if he knew they would 
make his symptoms worse."7 
 
We conclude that, given the unusual facts of these cases, 
there is a significant risk that the jury misunderstood our 
model jury instructions to mean that the defendant was not 
criminally responsible if his mental disease or defect was 
caused by his prior chronic cannabis use or if he knew or should 
have known that his prior chronic cannabis use either caused his 
                     
7 In his concurrence, Justice Lowy argues that we should not 
limit this instruction to voluntary intoxication but should 
provide it whenever there is evidence that (1) the defendant has 
a mental disease or defect, (2) the defendant recently consumed 
drugs or alcohol, and (3) the defendant knew or had reason to 
know that this consumption could trigger or intensify his mental 
disease or defect so as to cause him to lack substantial 
capacity.  The facts of these cases illustrate the risk that 
would arise from adopting that as the general rule. 
 
There was evidence that the defendant knew that his use of 
cannabis would "set off other drugs" he had taken before, but 
only when he was "high" on cannabis.  There was no evidence that 
he knew that cannabis would have this effect when he was no 
longer high or when he went into withdrawal.  The instruction 
that the jury received, and which Justice Lowy would leave 
intact, would permit the jury to conclude that the defendant was 
criminally responsible because he knew or had reason to know 
that his "consumption" of cannabis would trigger or intensify in 
him a mental disease or defect that could cause him to lack 
substantial capacity, even though the defendant did not know 
that this could happen when he was no longer high. 
 
We leave open the possibility that a judge could revise 
this instruction if there was evidence that the defendant knew 
or had reason to know that his recent use of drugs or alcohol 
could send him "over the edge" even if he were not high or 
intoxicated.  But, as here, in the absence of such evidence, the 
risk of confusing the jury is far less if we limit this 
instruction to voluntary intoxication. 
31 
 
 
mental disease or defect or increased its severity.  In view of 
the substantial evidence in these cases that the defendant had a 
mental disease or defect and that he lacked substantial capacity 
at the time of the killing, we conclude that there was a 
substantial likelihood of a miscarriage of justice arising from 
the risk of such a misunderstanding, and that justice demands 
that the defendant's convictions be vacated and the cases be 
remanded for a new trial. 
4.  Other claims of error.  We reach the other claims of 
error in the event they arise at a new trial.  See Commonwealth 
v. Pleasant, 366 Mass. 100, 103 (1974). 
a.  Admission of evidence of defendant's drug dealing.  The 
defendant contends that the judge abused his discretion by 
admitting evidence of the defendant's drug dealing over the 
defendant's objection.  Saleh testified that the defendant told 
him that he had supported himself and his wife with earnings he 
made by selling cannabis, and that, prior to his admission to 
the psychiatric ward, he sold several pounds of cannabis for 
$6,000.  Saleh then offered the opinion that a person who 
"truly" has schizophrenia would not be able to transact with 
other drug dealers to buy drugs, sell drugs, or consume drugs.  
The judge instructed the jury that the evidence of the 
defendant's drug dealing could be considered as a factor that 
Saleh used to formulate his opinion, and was not offered "to 
32 
 
 
reflect on the character of the defendant."  The defendant did 
not object to the judge's limiting instruction. 
We conclude that the judge did not abuse his discretion in 
admitting this evidence with a limiting instruction, where the 
evidence was offered to support Saleh's opinion that, at the 
time of the killing, the defendant did not have schizophrenia or 
any mental disease or defect.  It "did not lie 'outside the 
bounds of reasonable alternatives,'" see L.L. v. Commonwealth, 
470 Mass. 169, 184 (2014), quoting Adoption of Mariano, 77 Mass. 
App. Ct. 656, 660 (2010), for the judge to conclude that the 
probative value of the evidence was not outweighed by the danger 
of unfair prejudice.  See Commonwealth v. Upton, 484 Mass. 155, 
170 (2020), citing Commonwealth v. Crayton, 470 Mass. 228, 249 
(2014). 
b.  Presumption of sanity.  In his final instructions, the 
judge instructed the jury that "[y]ou may consider the fact that 
a great majority of persons are sane and the probability that 
any particular person is sane."  In Lawson, 475 Mass. at 815 
n.8, three years after these cases were tried, we considered a 
comparable jury instruction and concluded that, "given the 
meager weight of this inference and the risk of juror confusion 
regarding the burden of proof, judges should not instruct juries 
regarding this inference."  We noted that, "[a]lthough it is 
probable that an individual selected randomly would be 
33 
 
 
criminally responsible for his or her acts, that same 
probability would not attach to the tiny subset of the 
population who are criminal defendants with a long history of 
mental illness who proffer a defense of lack of criminal 
responsibility."  Id. at 814.  This instruction should not be 
given at the retrial. 
Conclusion.  We vacate the judgments of conviction and 
remand the cases to the Superior Court for a new trial 
consistent with this opinion. 
 
 
 
 
 
 
 
So ordered. 
 
 
 
LOWY, J. (concurring).  I agree that we must reverse the 
defendant's conviction because of the error in the judge's 
instructions to the jury regarding voluntary intoxication.  I 
also agree with the bulk of the court's reasoning about the 
conditions under which a defendant may and may not assert the 
criminal responsibility defense.  The court states that if "the 
defendant knew or had reason to know that his consumption of 
drugs or alcohol would trigger or intensify a mental disease or 
defect that could cause the defendant to lose substantial 
capacity," either to appreciate the criminality or wrongfulness 
of his conduct or to conform his conduct to the requirements of 
the law or if he knew or had reason to know that the drug or 
alcohol consumption pushed the defendant over the edge into 
lacking substantial capacity, then he "is criminally responsible 
for his resulting conduct" (quotations omitted).  Ante at    , 
quoting Model Jury Instructions on Homicide 6-7 (2018).  See 
Commonwealth v. DiPadova, 460 Mass. 424, 432 (2011).  I agree. 
It is the next step of the court's reasoning with which I 
disagree.  Inexplicably, in reversing the defendant's 
conviction, the court removes the category of circumstances just 
discussed under which defendants may not successfully claim a 
lack of criminal responsibility defense:  defendants who, while 
no longer high or intoxicated, recently consumed drugs or 
alcohol knowing or having reason to know that that recent 
2 
 
 
consumption would trigger or intensify a mental disease or 
defect that pushed them over the edge into losing substantial 
capacity.  See ante at    .  The court modifies our case law and 
changes our model jury instructions to prohibit the lack of 
criminal responsibility defense only under circumstances "when 
[the defendant was] voluntarily intoxicated by drugs or 
alcohol."  Id.  This modification would entitle a defendant to a 
defense of lack of criminal responsibility in circumstances when 
he is neither intoxicated nor high when he committed the crime, 
no matter what he knew or should have known about how his recent 
consumption would trigger or intensify a mental disease or 
defect that would push him over to edge into losing substantial 
capacity at the time of the crime. 
 
Under our precedent and contrary to the court's opinion, 
however, we are concerned not only with a defendant's behavior 
when he is intoxicated, or "drunk or high," at the time of the 
crime, ante at    , but also when the intoxicating effects of 
that recent consumption cause the defendant to lose substantial 
capacity.1  The court agrees that the defendant cannot claim the 
                     
 
1 Indeed, we have distinguished between intoxication, which 
requires a level of drug use that substantially impairs an 
individual's judgment, see Commonwealth v. Brennan, 399 Mass. 
358, 359 (1987) (defendant consumed "beer, wine, and a 'couple 
dozen rum and cokes,' took valium and smoked" cannabis on day of 
murder), and consumption, which need not impair the defendant's 
judgment so long as it triggers or intensifies a defendant's 
mental disease or defect.  See Commonwealth v. DiPadova, 460 
3 
 
 
lack of criminal responsibility defense where the source of the 
lack of substantial capacity is drug use, not a mental disease 
or defect.  See id. at    .  But the source of the lack of 
substantial capacity is only half of the equation; we also must 
look at the defendant's knowledge when drug use and mental 
diseases or defects interact.  See DiPadova, 460 Mass. at 437.  
A defendant who consumes drugs close in time to his commission 
of the crime, and who knew or had reason to know that his recent 
drug use would send him over the edge either by causing or 
intensifying a mental disease or defect that would lead him to 
lose substantial capacity, should be criminally responsible, no 
matter whether he is still intoxicated or high at the time of 
the crime.  See id. at 439 (Appendix). 
 
A hypothetical example will help explain my concern with 
the court's decision.  Imagine a defendant who knows that if he 
consumes any opiates, he will lose substantial capacity, and not 
                     
Mass. 424, 427 (2011) (conflicting evidence whether defendant 
consumed drugs before or after murder); Commonwealth v. Sheehan, 
376 Mass. 765, 767 (1978) (no evidence of drug use on day of 
crime, but "blacked out" from resulting effects of heavy drug 
use that occurred during five days preceding crime); 
Commonwealth v. McGrath, 358 Mass. 314, 320 (1970) (instruction 
regarding defendant's consumption "on the day of the crimes or 
the few days before the crimes" was proper).  See also People v. 
Travers, 88 Cal. 233, 239-240 (1891) ("settled insanity produced 
by a long-continued intoxication affects [criminal] 
responsibility in the same way as insanity produced by any other 
cause.  But it must be 'settled insanity,' and not merely a 
temporary mental condition produced by recent use of 
intoxicating liquor" [emphasis added]). 
4 
 
 
while he is just intoxicated or high, but also while his recent 
consumption of drugs still affects him physiologically and 
psychologically.  Imagine further that the defendant knows that 
such consumption will cause him to become violent because the 
opiate use "triggers or intensif[ies]" his mental disease or 
defect even after the intoxicating effects of the opiates have 
dissipated.  DiPadova, 460 Mass. at 439 (Appendix).  The 
defendant decides to consume the opiates nonetheless, resulting 
in his predictable loss of substantial capacity that outlasts 
the intoxicating effects of his consumption by hours or even 
days.  He thereafter kills someone while no longer intoxicated 
or high, but while still lacking substantial capacity due to his 
recent consumption of opiates.  Under this scenario, why does it 
matter whether an individual is no longer "voluntarily 
intoxicated" at the moment of the crime if he knew or had reason 
to know that his recent consumption of opiates would trigger or 
intensify a mental disease or defect and he thereafter lost 
substantial capacity for precisely that reason?  That the 
defendant was no longer "intoxicated" at the time of the alleged 
crime should not insulate him from criminal responsibility 
5 
 
 
simply because the lack of substantial capacity outlasted the 
intoxicating effects of the recent consumption.2  See id.3 
 
The court recognizes the importance of recent consumption 
when it notes, in defining the contours of voluntary 
intoxication, that "a person without a mental disease or defect 
[is not] entitled to a criminal responsibility defense if he or 
she robs [a] convenience store in the throes of opioid 
withdrawal," ante at    , and by acknowledging that the "know or 
have reason to know" instruction applies to "the intoxicating 
effects" of drug use, id. at    .  But by limiting the 
instruction to "present [drug or alcohol] use," id. at    , the 
court precludes the Commonwealth from proving the criminal 
responsibility of a defendant who continues to lack substantial 
                     
 
2 I agree with the court that the criminal responsibility 
defense should be available to a person whose lack of 
substantial capacity results from a "drug-induced mental disease 
or defect" because, in that scenario, the defendant's mental 
disease or defect causes the lack of substantial capacity, not 
the intoxicating effects of his past drug use.  See ante at     
("it does not matter whether the disease or defect arose from 
genetics, from a childhood disease or accident, from lead 
poisoning, from the use of prescription medication, or from the 
chronic use of alcohol or illegal drugs.").  See Commonwealth v. 
Herd, 413 Mass. 834, 840-841 (1992). 
 
 
3 I do not lay out in detail the parameters of what 
constitutes "recent consumption," but the consumption here, in 
the light most favorable to the Commonwealth, may well fall 
within the meaning of the term.  There was evidence that the 
defendant was still dealing with the residual effects of drug 
use.  See Herd, 413 Mass. at 840 (voluntary intoxication 
"refer[s] to the intoxicating effects of the consumption of 
drugs"). 
6 
 
 
capacity after recently consuming drugs even after the 
"voluntary intoxication" wears off, and who knew or had reason 
to know that the lack of substantial capacity would result. 
 
I agree with the court that "[a] drug-induced mental 
disease or defect still constitutes a mental disease or defect 
for purposes of a criminal responsibility defense."4  Ante at    
, citing Commonwealth v. Herd, 413 Mass. 834, 840-841 (1992).  I 
have no interest in punishing addiction or holding a defendant 
criminally responsible because of some perceived moral 
shortcoming resulting from his prior drug use.  I also am not 
suggesting that our law should bar a person with a substance use 
disorder from asserting a criminal responsibility defense if he 
knows or has reason to know that chronic use of certain drugs 
increases the risk of certain psychological conditions.  And 
like the court, I am certainly not suggesting that somebody who 
uses drugs or alcohol, knowing that it may cause him to have a 
mental disease or defect sometime in the future, could not 
assert a lack of criminal responsibility defense.5  Rather, I am 
                     
 
4 If, however, the defendant's voluntary intoxication or 
recent consumption caused the defendant to lose substantial 
capacity, and not the defendant's drug-induced mental disease or 
defect, the defendant is not entitled to a lack of criminal 
responsibility defense.  See Sheehan, 376 Mass. at 770. 
 
 
5 The "knows or have reason to know" (or knew or had reason 
to know) instruction does not deal with such conditional 
examples where a person has abstract or general knowledge that 
drug use causes brain damage or could lead to a mental disorder.  
7 
 
 
simply stating that, consistent with our existing case law, a 
defendant who consumes drugs close in time to his commission of 
the crime, and who knew or had reason to know that that recent 
drug use would push him over the edge and would cause him to 
lose substantial capacity, should be criminally responsible.  
See Herd, 413 Mass. at 843 ("one who starts taking a drug or 
continues using it, knowing that it will [trigger or intensify 
in him] a mental disease or defect, is not entitled to" lack of 
criminal responsibility defense). 
 
As for the facts of these cases, it may be, even in the 
light most favorable to the Commonwealth, that there was not 
enough evidence for a jury instruction concerning the 
defendant's recent consumption.  Considering, however, that the 
Commonwealth's expert testified that the defendant suffered from 
"a substance-induced psychotic disorder and a cannabis 
withdrawal condition," that the cannabis remained in his system 
at time of the alleged crime, and that the defendant 
comprehended that cannabis use brought about hallucinations and 
delusions and that the use altered his brain chemistry and 
personality, the issue is at least a close one and may reemerge 
                     
The knowledge assessed by the jury must be tied to the specific 
lack of substantial capacity at issue.  See, e.g., DiPadova, 460 
Mass. at 428 (2011) (defendant knew drug use led to auditory 
hallucinations that told him to kill victim); Herd, 413 Mass. at 
842 (defendant knew cocaine use would lead to violence that 
occurred). 
8 
 
 
at retrial.  Whether it will be appropriate to provide the 
recent consumption instruction on retrial will be a decision for 
the judge to make, and it will depend on whether the 
Commonwealth can prove that the defendant's recent consumption 
of cannabis, and not any drug-induced mental disease or defect, 
caused the defendant to lack substantial capacity.  
Nevertheless, the facts and posture of these cases do not 
support the court's decision to eliminate the Commonwealth's 
ability to hold accountable a defendant who, although no longer 
intoxicated, knew or had reason to know that his recent 
consumption of drugs would trigger or intensify a mental disease 
or defect that causes him to lose or to lack the substantial 
capacity to appreciate the wrongfulness of his conduct or to 
conform his conduct to the requirements of the law.  See 
DiPadova, 460 Mass. at 437.