MPD and Insanity Defense (Legal)

I’m aware that Multiple Personality Disorder has been discussed many times here at the SDMB. I’ve searched the archives exhaustively and cannot discover any threads discussing whether MPD has ever been used successfully as an insanity defense in a legal trial. The failure to find any refererence herein may well be a factor of my incompetence rather than the absence of the information I seek. Googling gives much in the way of debate over whether the condition actually exists but no reference to its legal status.

Has MPD (not DID) ever been successfully used to prevent someone from going to gaol in a legal plea of insanity?

I’m not even going to look; the answer has to be “no.” “Insanity” is a legal term that has nothiing to do with typical mental illnesses. Either you are unable to perceive the difference between right and wrong, or you literally do not know what you are doing, or you are incapable of the mental state of guilt. MPD suits none of these.

Actually, there are a few cases of MPD’s being accquited on an insanity defense. Billy Milligan is the first and most well known; he was accquited of raping several women near Ohio State University. Supposedly a lesbian personality (one of 23) had perfomed the rapes. Crime Library has a discussion of Milligan and several others:

Well, I suppose nothing can stop the defense from asserting it, nor a jury from buying it. I was far too confidentin the system, and apparently in the ability of judges to perceive when they’re being snowed.

Why slam the judges?

If the defense raises a colorable question of fact, it’s for the jury to decide – on what basis might a judge exclude this sort of defense?

(underlining mine) But isn’t this the case in Billy Milligan’s case? His body performed the act, but Billy didn’t, and Billy didn’t know what his body was doing because he wasn’t using it at the time. It’s not possible to incarcerate the criminals (the lesbian personality and one other) without incarcerating 22 other innocent people. And I have to point out that “getting off” doesn’t mean they’re off wandering the streets - they were commited to psychiatric care for a decade before being released. That’s longer than a lot of rapists serve in jail. Now that they’ve been released (and still a multiple) they have not apparently committed another crime. Seems to me that this is indeed an example of “the system” working in a positive way.

These responses seem to indicate that you simply don’t believe that MPD exists, which was not the question in the OP, and seems better served in another thread, unless you have an expert opinion to add to the mix (ie. you’re a psychiatrist or psychologist - in which case, I’d love to hear more.) (IANAMod, just my 2¢)

Slight correction: in 1996, Billy was charged with criminal contempt of court for threatening a judge, apparently in connection with a case the state of Ohio had pending regarding his hospital bills. So change that line to “…they have not apparently committed another *violent * crime.”

Just 'cause you have MPD doesn’t mean you can’t be a jerk, I guess.

Work was started on The Minds of Billy Milligan (by Daniel Keyes–yes, that Daniel Keyes) as a movie, but Billy got weird (er, make that “became unstable”–no, that’s not it, um…“changed his mind!” No, wait…anyway, you get the idea) and squelched it. Daniel was disappointed that Billy couldn’t keep it together. There was talk (I don’t know how serious) that Brad Pitt would star.

Well what are the odds of having 23 personalities, all of them charming?

What a crock. You’re assuming that the law views “MPD” as the same thing as 23 separate people sharing a body. It doesn’t. A person like Mr. Milligan would certainly qualify as insane in the legal sense. He committed the crime, and he wasn’t able to perceive the difference between right and wrong, at least while he thinks he’s this other person.

MPD has been renamed dissociative identity disorder. Having known a few people with the disorder, I certainly believe it exists. I’m shocked it could be used as an insanity defense. If one of the personalities commits a violent crime, the only question should be whether that particular personality is legally insane (as Nametag said this is soley a question of distinguishing right and wrong). If they are, the verdict should be not guilt by reason of insanity followed by a long compulsory stay in a secure mental health facility. If the personality is found competent to stand trial and found guilty, they should be sentenced as usual. That the other people in the body are innocent does not matter. One of the folks in there has committed a violent crime and society must be protected.

Other than the first sentence, please replace “personality” with “alter”. I blame force of habit, and the continued use of the term personality in the media.

It may be worth noting that, since the 1970s, many states have changed the law on the insanity defense, making it narrower and/or harder to assert. Many of these changes were prompted by the uproar over John Hinckley’s acquittal, by reason of insanity, for the shooting of Ronald Reagan.

OK, taking things in order:

  1. I slam the judges because in at least one case, a judge made the finding of fact, and also because it’s the judge’s job to make the law clear to the jury.

  2. As was eventually mentioned, the DSM-IV calls it DID; this demonstrates the paradigm change in clinical psychology. The DID diagnosis does not recognize the existence of multiple personalities. I go a bit beyond the APA, though; I regard the personalities to be psychotic delusions, not splinters of a main personality. They may be organic or traumatic in origin, possibly a type of schizophrenia. I don’t claim to be an expert, but I do believe that the law has no business declaring the innocence of any person containing a mens rea.

  3. Hack her to death with a kitchen knife, or ask your mother to do it.