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Mental State at Time of Offense (MSO) Evaluation

Need consultation for your case? Are you unsure whether your client was insane at the time of the offense and whether or not you have a viable defense? A full evaluation to assist in determining whether an individual meets the legal definition of insanity is available.

Click the following Services below to get further information on the MSO Evaluation Services.



Mental State at Time of Offense Evaluation Services

What is a mental state at time of offense (MSO) evaluation?
What is insanity?
What is in the report?

What is a mental state at time of offense (MSO) evaluation?

An MSO evaluation consists of a series of three interviews. The first focuses upon historical information about the defendant, the second focuses upon the offense of their mental state at that time and the third assesses the defendant's present mental state.  Although all three sections are important, the first section appears to be one of the most important aspects. Understanding an individuals historical background and how it pertains to his mental state at the time of the offense appears of most importance. Understanding an individual's history of bizarre behavior, disturbance of affect, episodic disorders, and any suspected neuropsychological defects should be evaluated. A rating system for comparing the defendant's self-reports with police reports, attorney notes, and any other developmental histories is a must to determine the facts. The forensic examiner, hence, becomes an investigator for the courts and may spend time reviewing collateral information and interviewing other third party persons. Factors such as planning the offense, awareness of criminality, and self-control are rated along with an analysis of the collated information. Malingering is assessed, as is the possibility of brain damage. DSM-IV-TR disorders are identified, and cognitive & behavioral control are assessed. An MSO evaluation assesses if a mental disease or defect caused a cognitive impairment at the time of the offense. The M'Naghten test permits exculpation on either of two grounds: (1) when the defendant did not know the nature and quality of the criminal act and (2) the defendant did not know that the act was wrong. An individual can also be found insane if he presented with "irresistible impulse," and due to mental disease or defect, lost control over their actions at the time of their offenses.

What is insanity?

Insanity is a legal concept, not a clinical concept.  The insanity defense, also called Not Guilty by Reason of Insanity (NGRI) is a 13th century legal tradition or paradigm where some peoples' minds are seen as so deranged, diseased, or defective that they are not sure what they did and normal grounds for responsibility and punishment don't apply.  The burden of proof for insanity almost always rests with the defense, so insanity is a subtype of "affirmative defense" where the defense must shoulder the burden of proof.  Other affirmative defenses include self-defense, entrapment, duress and provocation. Normally, an affirmative defense is so-named because it allows the defense to just raise, or affirm the defense, forcing the prosecution to rebut it.  Most legal rules preclude the possibility of ever going back to a plea of innocence, or any other kind of plea, once the decision is made to adopt the insanity defense. The insanity defense basically states that a crime was committed, although there was an inability to prevent it by way of consciousness and voluntary control was not in place.  

The role of a psychologist is usually to provide a Mental State at Time of Offense (MSO) evaluation which, in most cases, is often ordered and conducted simultaneously with a competency evaluation. This is done to cover all the bases or to determine competency first, since competency can delay the proceedings. Time and costs for providing these two evaluations, however, are high. A significant difference between a competency hearing and an MSO or insanity evaluation is that in an MSO evaluation the psychologist is required to obtain considerable information on the defendant's version of events at the time of offense. In a competency hearing, obtaining that information is important and helpful, although not legally required or imperative.  Another significant difference is that a defendant can only be tried once for insanity (otherwise it would violate the double jeopardy laws) while they can be tried in court again for competency.   

The legal definition and practice of the insanity defense varies from jurisdiction to jurisdiction.  The federal government has revised its approach a number of times in the last 50 years.  Some states don't recognize an insanity defense, but allow mental state issues to be raised as a possible mitigating factor at sentencing called diminished capacity. This is allowable in all states.  Approximately half of the states allow something akin to a temporary insanity defense, technically called diminished responsibility. Some states also have another legal option aside from insanity, called Guilty But Mentally Ill (GBMI).

The so-called "modern" era of the insanity concept began in 1843.  Prior to that, there were other relatively unimportant procedures such as the "wild beast" test and the "begat" test (if capable of procreation).  Most textbooks refer to the following as significant historical placemarkers in the evolution of the modern insanity defense. The characterizations given below are not meant to be used as legal guidelines and should be used as illustrations and examples for informative purposes:

  • M'Naughten rule -- In 1843 the "Wild beast" test ended and ushered in the "right/wrong" test. This test consisted of three prongs: 1) an unsound mind; 2) not knowing what they were doing; and 3) an inability to appreciate the wrongfulness of the act. M'Naughten is considered a cognitive-based standard which doesn't address the issue of volition (free will, or the ability to choose not to do wrong).

  • Irresistible Impulse test -- In 1899 a short-lived "add-on" to the M'Naughten rule allowed insanity to include any impulse control situation where a person who knew the difference between right and wrong could simply not resist a temptation or emotion-based impulse. This test assists in measuring volition, although it should not be confused with a sudden outburst. An impulse as a result of months of brooding or if a person has a very disturbed and emotional personality does not completely account for irresistible impulse. This concept is vague and careful scrutiny of this concept when performing an evaluation is needed.

  • Durham rule -- The 1954 test created by Judge David Bazelon in Durham v. U.S. presumes that insanity is a mental disease or defect and can be agreed upon by experts. If the person is deemed insane if the criminal act was a product (product test) of a mental disease or defect. This resulted in large number of people with untreatable personality disorders being found insane.
  • McDonald modification of Durham -- A 1962 District Court case in D.C. narrowed the definition of mental disease or defect to only those conditions which substantially impaired mental or emotional processes, and more importantly, impacted one's behavioral controls.
  • Washington revision of the product test -- A 1967 ruling by Judge Bazelon in which mental health experts would no longer be allowed to render an opinion (ultimate opinion) about any causal connection between mental illness and criminal behavior. Experts would limit themselves to a description of the illness, how the person adapted to it and whether or not they were suffering from the illness at the time of the offense.
  • ALI/Brawner standard -- The 1972 adoption of the American Law Institute's recommendation from 1961 stated that insanity be defined as the presence of a mental disease or defect (specifically excluding personality disorders and diminished capacity conditions) and where either: (1) a substantial capacity to appreciate the wrongfulness of the act exists; or (2) an inability to conform or control one's behavior to the requirements of the law exists (known as the volitional prong). Critics argue that this is just M'Naughten revisited or revised.
  • 1982 Hinckley verdict -- The aftermath of the Hinckley acquittal lasted three years with Congress and several states challenging the volitional prong of the ALI test. It shifted the burden of proof with insanity affirmative defenses and supplementing the NGRI verdict with a GBMI (Guilty But Mentally Ill) verdict.
  • Jones v. U.S. (1983) -- a Supreme Court case ruled that there was no absolute connection between the length of time for confinement to treat a mental disorder and the underlying (presumed) length of time for punishment and the burden of proving one is no longer a danger to self or others, or safe to release, falls on the defendant.

  • Insanity Defense Reform Act of 1984 -- This act was a return to strict M'Naughten test in a number of ways because it requires a "severe" mental illness, holds that psychosis (and a delusional system) alone is not the same as insanity, prohibits experts from testifying on the ultimate issue, and establishes clear and convincing proof as the standard by which the defense needs to prove insanity. A psychologist should not state conclusively that an individual was insane, because it is considered a legal term and not a psychological term. A psychologist should simply establish or assist to clarify the individual's mental state at the time of the offense.
  • Foucha v. Louisiana (1992) -- A controversial Supreme Court ruling which said that even people with dangerous personality disorders could be released if the mental disorder that declared them insane in the first place went into remission or was "cured." This is usually referred to as a restoration to sanity. Most states redefined such personality disorders as serious mental illnesses and kept such people in confinement, especially if they had a treatment program or civil commitment procedure which could justify it.       

Many evolutionary changes have evolved since the above historical placemarkers. For example, most states and the federal government now use a preponderance of the evidence standard for insanity determinations; "backdoor" commitments via stipulations, dangerousness, and justifications for treatment are still common; sexual predators are for the most part basically prohibited from using any insanity defense; It is reported that GBMI offenders still receive no better treatment than NGRI offenders.

What is in the report? The report contains a social history, mental status examination and test results that detail extensively the personality make up of a particular individual. It contains extensive information from collateral sources and some clarification and rationale is given to the courts to how an individual may have presented mentally at the time of the crime.

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