"Excited delirium" is a contested label often invoked when someone dies during or shortly after police restraint. California has barred it. UK police have dropped it from their forms. Yet the term — and its successor, "acute behavioural disturbance" — runs through more than 20 coroners' Prevention of Future Death reports. Because those reports are now searchable together, you can read them.
"Excited delirium" describes extreme agitation, apparent insensitivity to pain, and physical distress, and is characteristically applied to people who die suddenly while being restrained. Its critics argue it functions less as a diagnosis than as an explanation of death — one that locates the cause in the person's body rather than in the force used against them.
The term emerged in 1980s Miami, where the medical examiner Charles Wetli attributed the deaths of 32 Black women to a syndrome he called "excited delirium" — supposedly a reaction to cocaine and sex. The women were later found to have been murdered. That origin is now cited as an example of the concept's shaky and racially loaded foundations. It has never been recognised as a diagnosis by the mainstream medical establishment: it does not appear in the World Health Organization's classification or the DSM, and the American Psychiatric Association, the American Medical Association and the National Association of Medical Examiners do not recognise it. In 2023 the American College of Emergency Physicians withdrew the 2009 paper that had lent the term much of its clinical credibility.
In the UK the term more often used is acute behavioural disturbance (ABD), presented as a description of a cluster of signs with several possible causes rather than a diagnosis, and partly as a move away from "excited delirium". Critics counter that ABD inherits the same problems under a more clinical name — the same thin evidence base and the same racialised pattern of use. The Royal College of Psychiatrists, in a 2021 intervention it later revised after objections and now addresses in its position statement PS02/22, questioned the terminology's evidential basis and its disproportionate application to Black men. Research by King's College London found ABD was about twice as likely to be recorded in the mental-health assessments of Black patients as of White ones.
In October 2023 California — prompted by the 2020 death of Angelo Quinto, whose death certificate had cited "excited delirium syndrome" — became the first US state to bar the term as a cause of death, prohibiting its use in death certificates, autopsy reports and police reports (effective January 2024). Colorado has since done the same.
In the UK, a March 2024 investigation by the Observer, the charity Inquest and the Royal College of Psychiatrists found the terms had been cited as a cause of death or contributing factor in at least 44 restraint cases since 2005. Inquest's executive director, Deborah Coles, said they had been used "to try and downplay the significance of the police use of force and explain away the role of dangerous and negligent restraint". The following month the police watchdog (the IOPC) removed "excited delirium" from the form forces use to refer such deaths — but kept "acute behavioural disturbance", which is why some argue the underlying idea simply persists under a more clinical name.
This is where deathlessons.org can add something concrete. A Prevention of Future Death report is written when a coroner believes a death exposes a risk of further deaths. Search the full text of every published report and you find these terms threaded through more than 20 of them, spanning 2013 to 2026 — sometimes as a mechanism cited at inquest, sometimes in the coroner's own concerns about how the label is used, sometimes in the training and guidance the reports scrutinise.
A few, with the coroner's report a click away:
A term can be dropped from a form in a day. Whether the thinking behind it changes is a slower, more contested question — and it plays out one inquest at a time, in documents that were, until recently, almost impossible to read together. Prevention of Future Death reports exist so that a lesson learned in one death can prevent the next. On a subject like this, being able to lay the reports side by side is not a convenience; it is the whole point.
Further reading — the Observer/Guardian reporting this post draws on: the March 2024 investigation, families' concerns, the IOPC form change, the 2021 medical-guidance row, and the California ban.