In State v Darnall (1980),11 a defendant charged with murdering his father pleaded NGRI due to having multiple personalities. The court found that the defendant likely was malingering his alters, and even if they did exist, having alter personalities was not necessarily a mental disease that would preclude responsibility for the murder.
In State v Grimsley (1982),12 the defense used NGRI due to multiple personalities in a drunk driving case. The court ruled that it is immaterial what state of consciousness or personality the defendant was in as long as the personality controlling the behavior was conscious and aware of his or her actions.
In Kirkland v State (1983),13 attorneys for a woman who committed a bank robbery asserted an insanity defense based on a psychogenic fugue, which is sudden, unexpected travel away from home accompanied by inability to recall one’s past and confusion about identity or assumption of a new identity.3 The court found that the law adjudges criminal liability according to the person’s state of mind at the time of the act and will not inquire whether an individual possesses other personalities, fugues, or even moods in which he would not have performed the crime.
In State v Jones (1988),14 the court found the defendant guilty of murdering a woman he met at a bar despite expert testimony that his multiple personalities “paralyzed” him from knowing right from wrong.
More recently, courts have rejected the admissibility of DID evidence, including expert testimony, because the scientific evidence failed to meet reliability standards, and therefore is not ultimately useful to the judge or jury. In State v Greene (1998),15 the defendant claimed that 1 of his 24 alters was responsible for killing his therapist. The Supreme Court of Washington affirmed that evidence of Mr. Greene’s DID, including expert testimony, was not reliable and not admissible.
Similarly, in State v Lockhart (2000),16 Mr. Lockhart contested his conviction of first degree sexual assault on the basis that he was not permitted to present evidence of DID to support his insanity defense. The West Virginia Court held that the diagnosis of DID was speculative and therefore did not meet reliability standards for evidence.
Table 2
Using dissociative identity disorder* as a basis for not guilty by reason of insanity
| Case | Year | Charge | Defense | Court ruling |
|---|---|---|---|---|
| State v Milligan10 | 1978 | Rape | NGRI-MPD | Lack of an integrated personality meant the defendant was not culpable |
| State v Darnall11 | 1980 | Murder | NGRI-MPD | Multiple personalities do not preclude criminal responsibility |
| State v Grimsley12 | 1982 | Drunk driving | NGRI-MPD; primary personality had no control over the ‘alter’ | State of consciousness or personality of defendant is immaterial |
| Kirkland v State13 | 1983 | Bank robbery | NGRI-psychogenic fugue | Law does not inquire about other personalities, fugue states, or moods in cases of criminal liability |
| State v Jones14 | 1988 | Murder | NGRI-MPD | Alter personalities will not be an excuse for inability to distinguish right from wrong |
| State v Greene15 | 1998 | Murder | NGRI-DID; primary personality was ‘unconscious’ | Evidence of DID, including expert testimony, was not admissible because it did not meet reliability standards |
| State v Lockhart16 | 2000 | Sexual assault | NGRI-DID | DID was not allowed into evidence by the West Virginia Court due to lack of scientific evidence |
| *Dissociative identity disorder formerly was referred to as multiple personality disorder DID: dissociative identity disorder; MPD: multiple personality disorder; NGRI: not guilty by reason of insanity. | ||||
Evaluating DID
Because the courts may ask psychiatrists to provide expert opinion on DID to assist with legal rulings, clinicians must remain vigilant to the possibility of DID as well as to defendants who may malinger multiple personalities to evade punishment. In such situations, factors to consider include the mental status examination, data and history collection, collateral information, criminal background, mental health history, history of abuse, and objective assessment tools.
Extensive field testing has shown that the Structured Clinical Interview for Dissociative Disorders (SCID-D) has good reliability and excellent validity.17 The SCID-D allows a trained interviewer to assess the severity of 5 dissociative symptoms: amnesia, depersonalization, derealization, identity confusion, and identity alteration.17 Other tools that may help assess a patient with suspected DID are listed in Table 3.
Patients who commit criminal acts while in a dissociated state may assert a defense of NGRI due to DID, but rarely has this defense been successful. Although a patient may have distinct personalities that control his or her behavior, this condition does not preclude criminal responsibility.
The role of hypnosis in evaluating DID is controversial. The introduction of pseudo-memories and potential for iatrogenic DID may complicate the clinical presentation and subsequent diagnosis.18
Table 3
Tools for diagnosing dissociative identity disorder
| Structured Clinical Interview for Dissociative Disorders |
| Dissociative Disorder Interview Schedule |
| Dissociative Experiences Scale |
| Childhood Trauma Questionnaire |