Amnesia and
Criminal Competencies
Forensic Neuropsychology
Marie Schroder
June 8, 2006
Amnesia

Conceptualized by neuropsychologists
 Profound deficit in acquisition, retention,
or retrieval
 Anterograde/ Retrograde
 Amnesic syndrome
 Anatomical substrate
 MTL, Diencephalon, Basal Forebrain
Amnesia in the Legal System

General Misconception: Amnesia is tantamount
to having a bad memory

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amnesia is “simply the inability to remember”
(Thomas v. State, 1975)
“amnesia is present to some degree in everyone”
(State v. Molnar, 1980)
Scientific basis may be misunderstood

“in most cases of amnesia due to physical trauma, there is
not only a loss of personal memory, but also an inability to
recall acquired facts, and a loss or impairment of the power
to use words” (American Law Report, 1972)
Types of Amnesia


In the large majority of criminal cases, loss of
memory either has a functional origin or concerns
only a single critical event (Schacter, 1986)
Organic amnesia

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
Alcohol related
Head injury
Epilepsy
Functional amnesia

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Dissociation
Fugue
Organic Amnesia

Alcohol related amnesia
 Alcoholic blackout – onset is abrupt and
duration usually confined to a few hours
 Long-term alcoholism resulting in
chronic memory disorder
Organic Amnesia

Epilepsy
 Typically complex partial seizures
 Automatism - behavior that is executed
involuntarily without consciousness or
intention
Organic Amnesia

Head injury: sustain head injury in the
course of the offense or subsequent to it
 May suffer a retrograde amnesia for the
act and prior events
 May suffer anterograde amnesia
Functional Amnesia
Cannot be understood in terms of brain
dysfunction
 Sudden inability to remember personal
information (often restricted to incidents
surrounding critical event)
 Cause is thought to be one or more
emotionally disturbing or traumatic events

Functional Amnesia

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Dissociation
 Dissociation at material time
 Fugue – dissociative state characterized by
amnesia and physical flight from environment;
often assumption of new identity
 Multiple Personality
Limited amnesia – pathological forgetting of a
specific episode
 State dependent
What defendants are most likely to claim amnesia?

Amnesia is a common claim in those charged with
homicide or other crimes of serious violence

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estimates for amnesia for homicide range from 23-65%
Taylor and Kopelman (1984) studied men
remanded for violent and nonviolent offences
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Amnesia claimed by nearly 10% of sample, all of whom
committed crimes of violence
Amnesics had concomitant psychiatric disorder
(e.g., depression, alcohol abuse, schizophrenia)
Strong association between amnesia and offences in which
victim was someone to whom the offender had been close
Criminal Competencies
Competency to confess
 Competency to plead
 Competency to waive right to counsel
 Competency to stand trial*
 Competency to be sentenced
 Competency to waive further appeal
 Competency to be put to death

Competency to stand trial
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Dusky v. U.S. (1960) emphasizes present ability
Amnesia should be considered in competency
evaluation
 Can a defendant establish a reasonable defense
if he is amnestic for the offense?
 General memory problems more likely to be
probative for competency issues than amnesia
for offense
 Courts more receptive to temporary amnesia
Wilson v. U.S. (1968)

Federal Court of Appeals concluded that amnesia
did not eliminate competency to stand trial.
They enumerated 6 factors determining the
effects of amnesia on competency:
1. The extent to which amnesia affected the
defendant’s ability to consult with and assist
his lawyer*
2. The extent to which the amnesia affected the
defendant’s ability to testify in his own
behalf*
Wilson v. U.S. (1968)
3. The extent to which evidence relating to the crime
itself or to any reasonably possible alibi could be
reconstructed from sources other than the
defendant’s memory
4. The extent to which the government assisted the
defendant and his counsel in that reconstruction
5. The strength of the prosecutor’s case, i.e., whether
the case was strong enough to negate all
reasonable hypotheses of innocence
6. Any other facts and circumstances that would
indicate whether the defendant had a fair trial
Case Example
People v. Palmer (2000)
 Possession of large quantity of marijuana
 Subsequent on-the-job accident resulting in multiple
skull fractures
 Claimed amnesia for event leading to charges; claim
accepted by court appointed evaluator
 Was he incompetent to stand trial because he was
unable to assist in his defense, as counsel claimed?
 NO: Understanding of proceedings present;
Found competent to stand trial and convicted
Other criminal issues
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Actus Reus
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Mens Rea
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Excludes automatism: Courts have generally found that
individuals are not criminally responsible for acts committed
during an epileptic seizure
Amnesia does not affect responsibility for actions, unless
person additionally falls under insanity standard
“disease of mind” argument successful in some cases of
amnesia due to long-term alcoholism
Diminished Capacity

Amnesia may preclude specific state of mind for crime
charged (e.g., manslaughter rather than 1st degree murder)
Malingering? Amnesia can be feigned…

Evaluating legitimacy
 Defendant’s behavior
 Nature of memory loss (onset, consistency)
 Interview procedures
 Psychophysiological
 Objective tests
 Symptom validity test**
Summary
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Legal system needs education about amnesia
Courts have generally ruled that amnesia is not
sufficient to establish incompetency to stand trial
Skepticism regarding genuineness of claims of
amnesia
Courts beginning to ask questions of
psychologists regarding the effects of amnesia and
the possibility of feigning memory loss
References
Denney, R. L. (2005). Criminal forensic neuropsychology and assessment of competency. In
G. J. Larrabee (Ed.), Forensic Neuropsychology: A Scientific Approach (pp. 378-424). New
York: Oxford University Press.
Denney, R. L., & Wynkoop, T. F. (2000). Clinical neuropsychology in the criminal forensic
setting. Journal of Head Trauma Rehabilitation, 15, 804-828.
Howard, C. (1990). Amnesia. In R. Bulglass & P. Bowden (Eds.), Principles and Practice of
Forensic Psychiatry (pp. 291-298). London: Churchhill Livingstone.
Melton, G. B., Petrila, J., Poythress, N. G., & Slobogin, C. (Eds.). (1997). Psychological
evaluations for the courts: A handbook for mental health professionals and lawyers (2nd Ed.).
New York: The Guilford Press.
Miller, R. D. (2003). People v. Palmer: Amnesia and competency to proceed revisited. The
Journal of Psychiatry & Law, 31, 165-185.
Rubinsky, E. W., & Brandt, J. (1986). Amnesia and criminal law: A clinical overview.
Behavioral Sciences & the Law, 4, 27-46.
Schacter, D. L. (1986). Amnesia and crime: How much do we really know? American
Psychologist, 41, 286-295.
Taylor, P. J., & Kopelman, M. D. (1984). Amnesia for criminal offences. Psychological
Medicine, 14, 581-588.