LAS VEGAS, NV - JANUARY 17: Taser International's X2 two-shot Taser for law enforcement. (Ethan Miller/GETTY IMAGES)

NEARLY THREE months after a mentally ill inmate died, following an incident in which a guard at the Fairfax County jail shot her four times with a Taser while she was handcuffed, the Virginia medical examiner has ruled on her official cause of death: “excited delirium associated with physical restraint including use of conducted energy device.”

Translated into everyday language, the coroner found that the fact that Natasha McKenna was shot repeatedly with a stun gun while she was shackled was part of the mix leading to her death. However, the primary factor, in the medical examiner’s view, was a syndrome known as “excited delirium.”

That conclusion is troubling for several reasons. Medical examiners around the country have cited “excited delirium” as a cause of death with increasing frequency for the past decade or so, almost exclusively in cases involving civilians — arrestees and prison or jail inmates — who die in struggles with law enforcement officers.

Not infrequently, those deaths have involved the use of stun guns, usually Tasers, by police. Yet the fact of being shot repeatedly with a Taser has rarely been cited as a primary cause of death, and of course it is impossible to know definitively whether a person would have died anyway had she not been shot repeatedly with a stun gun.

The American Civil Liberties Union, among others, has cast doubt on “excited delirium” as a cause of death, suggesting it is used mainly to give cover to excessive use of force by law enforcement. Officers and coroners “are using ‘excited delirium’ as a means of whitewashing what may be excessive use of force and inappropriate use of control techniques by officers during an arrest,” Eric Balaban of the ACLU told NPR in 2007.

That point is reinforced by the fact that neither the American Medical Association nor the American Psychiatric Association appears to recognize “excited delirium” as a medical or mental health condition, according to an online search of each organization’s Web site. Outside of the medical examiner’s profession, the term does not seem to occur in medical textbooks.

No one suggests that the guards who shot Ms. McKenna repeatedly with a stun gun intended to kill her. (Hence the medical examiner’s classification of the “manner” of her death as “accident” — as distinguished from homicide, which would imply intentionality.) The question, though, is to what extent repeatedly shooting her with a Taser contributed to her death; that question is not entirely resolved by the medical examiner’s conclusion.

Nonetheless, the finding should provide the final information needed by police looking into the incident, enabling them to turn over the results of their investigation to prosecutors. That, at least, counts as belated progress in the McKenna case.