‘Excited delirium’: California Bans Term as a Cause of Death

California has become the first U.S. state to ban the use of “excited delirium” as a cause of death, rejecting a term that prominent medical associations have said is rooted in racism and is often used to justify the deaths of people in police custody.

The legislation, which Gov. Gavin Newsom signed on Sunday, prohibits coroners or medical examiners from using the term on death certificates. It had passed California’s State Assembly with unanimous support and received final legislative approval last month.

Michele Heisler, the medical director of Physicians for Human Rights, an advocacy group based in New York, called the signing of the bill a victory for “justice, police accountability, human rights and health.”

“This baseless concept can no longer be used in California to absolve law enforcement for deaths in custody, misinform responses to people facing medical and behavioral crises, or block access to legal remedies,” Dr. Heisler said in a statement.

Police officers and forensic pathologists have often used the term “excited delirium” to describe people who become distressed or aggressive from a mental illness or the use of stimulants. The term was first used in a 1985 study on cocaine users. Reports of patients with similar symptoms appeared as early as the 19th Century, according to one study.

More recently, a number of major medical associations in the United States, including the American Medical Association and the American Psychiatric Association, have dismissed the term as pseudoscience. In March, the National Association of Medical Examiners became one of the latest to say that it should not be used as a cause of death.

When the American Medical Association announced its opposition to “excited delirium” in 2021, it said its decision had been based on reports that showed a pattern of using the term as “justification for excessive police force, disproportionately cited in cases where Black men die in law enforcement custody.”

The term has figured in a number of high-profile cases. One of the officers at the scene of the death of George Floyd in Minneapolis, for example, was heard in body camera footage saying that he was “concerned about excited delirium or whatever.” At the trial of one of the officers, Derek Chauvin, the prosecution went out of its way to pre-empt any argument by the defense that Mr. Floyd had been experiencing excited delirium.

The sponsor of the California legislation, Assemblyman Mike A. Gipson, a Democrat from Los Angeles, has said that he introduced it because he thought it was “absurd” that the term had been used to officially explain the death of Angelo Quinto, who died days after an altercation with police officers in Antioch, Calif., in 2020. Mr. Quinto’s family said in a wrongful-death lawsuit that two officers who had responded to a call from his sister knelt on his back for nearly five minutes to subdue him.

“Excited delirium has been used for decades to explain away mysterious deaths of mostly Black and brown people in police custody,” Mr. Gipson said in a statement on Wednesday. “We will not stand by and let bad actors get away with murder any longer.”

Several California-based associations representing police officers and emergency workers did not immediately respond to requests for comment. A 2014 article in the F.B.I.’s Law Enforcement Bulletin described it as “a serious and potentially deadly medical condition involving psychotic behavior, elevated temperature, and an extreme fight-or-flight response by the nervous system.”

A spokeswoman for the American Medical Association, Jennifer Sellers, referred questions about the new legislation to the California Medical Association, which did not immediately respond to a request for comment.