Role of Neuropsychological/Psychiatric Diagnosis in Mental State at time of

Offense (MSO) Evaluations

Bradley J. Daniels, M.S.

7/27/2006

Andrea Yates-”She So Crazy”

Outline

• Today I’ll talk primarily about the insanity defense since it “is the most commonly invoked doctrine relating to MSO” (Melton, Petrila, Poythress, and Slobogin, 1997, p. 186)

Common Misconceptions about the insanity defense

1.Lots of people use it2.Lots of people “get away with it”3.Those who get away with it get to

go free4.“Those people” are dangerous

Facts about the Insanity Defense

• Insanity defense used in approximately half of 1 percent of criminal cases

• Successful acquittals are “rarer than snake bites in Manhattan” (Perlin, 1992)

• Most successful insanity defenses are based on the presence of either a) mental retardation or b) severe psychosis

Relationship of Diagnosis to MSO Defense

• Psychoses and Personality D/Os• Severe psychosis usually required for the

insanity defense to succeed• Mild psychotic symptoms, or “temporary

insanity/psychosis” defenses much less likely to get acquittal

• Personality disorders also don’t get much success, especially antisocial PD

Relationship of Diagnosis to MSO Defense

• Epilepsy• Complex partial seizures of temporal lobe

origin most significant for legal purposes due to limbic system linkages

• Research shows relationship bw/ directed aggression and epilepsy “tenuous”

• In evals, use Walker criteria (Melton p.220)• Also, defense pretty much useless if defendant

was aware they had violent seizures and did nothing (e.g., taking AEDs) to prevent them from occurring

Relationship of Diagnosis to MSO Defense

• Hypoglycemic Syndrome• “Twinkie Defense”• Lyle stated “At the lower levels of blood sugar,

humans are effectively decerebrated and are capable of nearly anything they have ever thought of or seen out of others in fiction or elsewhere.”

• Symptoms have of this d/o have a pattern the examiner should look for including: documented history of prior episodes with symptoms similar to those displayed at the time of the crime, no planning or motive in the crime, no escape attempt made, and amnesia for the crime itself.

Relationship of Diagnosis to MSO Defense

• Dissociative Disorders

• DID, Amnesia, Fugue, and Depersonalization D/O• Multiple Personalities? Controversial topic• Most common in individuals (most often women) who

are emotionally immature, self-centered and dependent individuals with childhood abuse hx

• Presence of multiple alter personalities, with first usually showing up in childhood

• Symptoms usually will have been observed by third parties close to individual

• Since stress reaction, if suspects lives are essentially anxiety-free, be suspicious!!

Relationship of Diagnosis to MSO Defense

• PTSD• Notorious as potential basis for mental state defense,

particularly for defendants with combat-related trauma

• Problems with evaluating: 1) validity of diagnosis since mostly based on self-

report2) establishing retrospectively that a flashback

occurred3) interaction of drugs with PTSD confounds things

Relationship of Diagnosis to MSO Defense• PTSD• Criteria (from Sparr et al.) to look for:

1. Flashback behavior sudden, unplanned, and uncharacteristic of persons normal behavior

2. Hx of traumatic events re-enacted by flashback behavior

3. Defendant amnesic for all or part of episode4. Lack of motivation for flashback behavior5. identifiable stimuli in current environment which

are identifiable to combat environment aka triggers

6. Defendant unaware of behaviors7. Victim merely coincidental8. Patient has other symptoms of PTSD

Relationship of Diagnosis to MSO Defense• Genetics-XYY Syndrome

• Genetic abnormality leading to tallness, low intelligence, and aggressive or violent behavior

• MSO defenses based on XYY are very rare

• Some studies showed higher percentage of XYY’s found in prison than in normal population

• However, the research on the XYY individual may “at worst, be weakly disposed toward criminal activity” (Melton, 1997, p. 225)

Relationship of Diagnosis to MSO Defense• Impulse Disorders

• Inability to resist the drive to perform a behavior• Most common-kleptomania, pyromania, and

compulsive gambling• Difficult to evaluate b/c little systematic study of

impulse disorders exists• However, all three diag criteria have in common that

the behaviors can’t really be done for significant monetary gain.

Reliability and Validity of MSO Opinions

• Only a handful of reliability studies done, and methodology varied

• Research does suggest higher reliability when clinicians have forensic training and no a priori allegiance to either side

• Validity studies “practically nonexistent” (Melton, p.230)

• Although few out there, and once again methodology varies, respectable concordance rates have been found

MSO Evaluations

• One of the most useful tools a neuropsychologist can use in MSO evaluations is the Multiple Data Source Method (MDSM)

Multiple Data Source Model

The All-Important “Middle Row”-from Larrabee p. 426

• “The Middle row of the MDSM focuses on mental state, behavior, and motivation at the time of the alleged offense (or the row can theoretically represent any event in the past, such as retrospective study of competency to stand trial, enter a guilty plea, waive right to counsel, understand Miranda warning, and competence to confess).”

The role of the MDSM in MSO as told by ME

• A defendant’s self-reported history, including that of the defendant’s thoughts and actions during and around the time of offense, should be consistent with current mental state and MSO given nature of illness

• CORROBORATIVE SOURCES are key in attempting to accurately assess MSO

Warning from Larrabee p. 428

“Most of the time, defendants are willing to provide their perspective of their functioning at MSO if they are seeking a mental health defense. Occasionally, defendants will be unable to do so because of acute mental illness or significant neurocognitive deficits. Inability to provide self-report information does not necessarily eliminate the ability to determine MSO, but it often limits the opinion to some degree.”

Use the MDSM and Don’t Ignore Data!!!

•Case Example from Larrabee p. 436-438•28 year old male•MVA at 19 and possible TBI, brief LOC•Two years after accident, becomes police officer and joins SWAT•Highly decorated career•Goes through rough patch with very sick baby and financial debt•Diagnosed with PTSD and Major Depression•Robs bank, gets caught•Uses TBI as mental illness as defense

Case Example cont’d…

•Details of the bank robbery suggested the events were highly calculated, well planned, and well executed

•Despite these facts, NP tests showed cognitive impairment and therefore neuropsychologist (hired by the defense, by the way) ruled him impaired

Question

•So, given that most of MSO evaluations involve exhaustive records review, interviewing, and may or may not require any kind of neuropsychological assessment whatsoever, what do NP’s have to offer the courts that a non-NP couldn’t do?

Questions???