AILSA CHANG, HOST:

In opening statements, the defense for former Minneapolis police officer Derek Chauvin invoked the term excited delirium when talking about George Floyd's death. But there is no commonly accepted definition for excited delirium, even though police departments across the country often cite this term when people die in police custody. Here to talk with us about the controversy over this term is Rashawn Ray. He's a sociology professor at the University of Maryland and a fellow at the Brookings Institution. His research focuses on race and law enforcement.

Welcome.

RASHAWN RAY: Thank you.

CHANG: All right. Before we explore how this phrase has been used, can you just explain what symptoms tend to get labeled, quote, "excited delirium"?

RAY: Excited delirium is a syndrome to describe behaviors and symptoms that may include a range of things - I mean, including severe panic or distress, disorientation, disassociation, aggressiveness and then other things such as fast heartbeats or hallucinations, incoherent speech and oftentimes unexpected strength or violence and high body temperatures and as well as bizarre behavior, failure to respond to police presence and continued struggle despite restraint. But we can also imagine that someone might exhibit some of these symptoms if they've just had a gun pulled on them or if they were held down by multiple people for what they perceive to be no justified reason.

CHANG: Right. And to be clear, this term, excited delirium, it has no generally accepted definition in scientific literature, right? Like, some professional organizations recognize it, and some don't.

RAY: Exactly. Medical professionals are mixed but mostly on the side of it not being recognized. While it is recognized by some, particularly those in the emergency room, it is not recognized by the American Medical Association, the American Psychiatric Association or the World Health Organization.

CHANG: OK. So tell us how law enforcement has used this phrase, excited delirium, over the years.

RAY: Well, of late, we've seen it applied to not only George Floyd but Elijah McClain in Colorado, who was walking home from work and given ketamine that ultimately led to his death, as well as Manuel Ellis in Tacoma, Wash. All are Black men and follow a broader pattern of how, when and on whom excited delirium is applied.

A diverse group of neurologists wrote an article for Brookings' How We Rise on how excited delirium is misused to justify police brutality. They note that law enforcement officers are often taught that excited delirium is a condition characterized by the abrupt onset of aggression and distress and typically associated with illicit substance use but - and that often culminates in sudden death at the hands of police. This diagnosis, however, they argue, is that it's often misappropriated when it comes to medical terminology and is often used as a legitimate way to justify police brutality and to retroactively explain certain deaths.

And that's important for people because there are a handful of studies on this. In one Maryland study, the study found that excited delirium was applied in about 11% of deaths that occurred in police custody. In Miami, there were about 35 deaths attributed to excited delirium. And then in the '80s, there were 30 Black women who died from excited delirium, but police subsequently ended up attributing those to asphyxiation by a serial killer.

CHANG: Interesting. Well, in the minute or so we have left, you know, when law enforcement invokes excited delirium, phrases like superhuman strength or pain tolerance are often used as evidence for this diagnosis. When you hear that language, how do you feel it plays on certain racial stereotypes?

RAY: Well, my research suggests that a set of stereotypes about Black men in particular highlights this, from classroom settings to even sports. In an article that I published in the American Journal of Sociology with Dr. Steven Foy, we found that commentators were more likely to talk about darker-skinned players for their strength and size, despite the fact that lighter-skinned players were taller, weighed more and were larger. So these cultural and pathological deficits hearken back to pseudo-racism about genetic differences by race to justify the mistreatment of Black bodies and overall leads to stereotypes about Black men about being aggressive, unnaturally strong, emotionally unstable. And in policing, it speaks to one troubling stat - that Black people are 3.5 times more likely than whites to be killed by police when they're not attacking or have a weapon.

CHANG: Rashawn Ray is a fellow at the Brookings Institution.

Thank you very much for joining us today.

RAY: Thank you for having me.

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