Supreme Judicial Court of Massachusetts Vacates Conviction of Man who Committed Murder While in the Throes of a Psychotic Episode

Above: Defendant Aldo Dunphe during his 2016 trial — Image Source: Telegram

In October 2020, after hearing evidence of the effect of schizophrenia and psychosis on his mental state at the time of the crime, the Supreme Judicial Court of Massachusetts vacated Aldo Dunphe’s 2016 conviction for a murder he committed in the midst of a psychotic episode during his stay at a psychiatric hospital.

On November 1, 2013, 23-year-old Dunphe was voluntarily admitted to a psychiatric ward in Worchester, MA after suffering from a severe psychotic episode the night prior. On November 5, 2013, Dunphe violently attacked a fellow patient in the psychiatric ward who, several days later, died from his injuries. Dunphe was charged with first-degree murder.

A medical expert hired by the defense testified that at the time of the killing Dunphe “was in the throes of an acute psychotic episode with a diagnosis of schizophrenia, and . . . in his delusional state. . . perceived the victim as an imminent threat.” In his first interview with police, Dunphe admitted to attacking the victim and said that his reason for doing so was because “the victim was his [biological] father who had threatened to kill him and was keeping him in the psychiatric ward against his will.” Dunphe’s counsel argued that Dunphe “lacked the substantial capacity at the time . . . to appreciate the wrongfulness of his conduct [or] to conform his conduct to the requirements of the law” and therefore he lacked criminal responsibility.

A jury found Dunphe guilty, and he was sentenced to life without the possibility of parole. On appeal, Dunphe’s defense alleged that the instructions given to the jury regarding criminal responsibility were misleading and resulted in a “substantial likelihood of the miscarriage of justice.”

Dunhpe’s heavy cannabis use since the age of 18 was not disputed, but there were disagreements over the origins of Dunphe’s psychosis and the role that cannabis played. The expert for the defense testified that while Dunphe could have been suffering from cannabis withdrawal syndrome at the time he carried out the attack, “such withdrawal alone could not account for the defendant’s series delusions and hallucinations.” Contrarily, the Commonwealth’s expert opined that “at the time of the killing, the defendant did not suffer from schizophrenia or another delusional disorder, but rather a ‘substance-induced psychotic disorder and a cannabis withdrawal condition’” which he stated, “did not qualify as a mental disease or defect.” Further, he stated that Dunphe’s long-term cannabis use had likely caused his schizophrenia and posited that Dunphe even knew the psychotic effects cannabis had on his brain, citing a previous conversation that Dunphe had with state troopers in which Dunphe said “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.”

The Supreme Judicial Court of Massachusetts ultimately agreed with Dunphe, concluding that the judge’s jury instructions during Dunphe’s May 2016 trial did in fact “create[] a substantial risk of juror confusion regarding the law of criminal responsibility.” On October 7, 2020, they vacated his conviction and remanded his case to the Superior Court for a new trial. In its opinion they stated, “What our case law declares, but our model jury instructions do not, is that if a defendant has a mental disease or defect, 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. A drug-induced mental disease or defect still constitutes a mental disease or defect for purposes of a criminal responsibility defense.”

Key words: schizophrenia, psychosis, cannabis, criminal responsibility, Massachusetts

Citation: Commonwealth v. Aldo W. Dunphe, 485 Mass. 871 (2020)

This post is the 20th post as part of an ongoing Center for Law, Brain & Behavior (CLBB) series tracking the latest developments in law and neuroscience cases. To see previous posts about recent cases, see the full case archive on the CLBB website. To see updates on legal scholarship, see the Neurolaw News, hosted by the MacArthur Foundation Research Network on Law and Neuroscience. This project is made possible through support of the Dana Foundation.




at Mass General Hospital, Harvard Medical School

Love podcasts or audiobooks? Learn on the go with our new app.

Recommended from Medium

Our Justice System Needs an Update—an Update that Goes Against the Law

Relief and Resolve in the Derek Chauvin Verdict

Compassionate Release Denied for Defendant with Neurological Deficits from Brain Tumor

Dershowitz’ Lawsuit Against CNN Is Still Based On A Big Lie

Utah Newlyweds Found Dead — Unsolved Double Homicide

Jury Summons and Relief

One Vote for Justice

Toledo Police officer killed in standoff with suspect

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Center for Law, Brain & Behavior

Center for Law, Brain & Behavior

at Mass General Hospital, Harvard Medical School

More from Medium


Help People Think Better, Don’t Tell Them What to Do!

On Existence