Criminal Responsibility

Expert Witness: Legal Defenses for Criminal Responsibility

For a person to be found guilty of a crime, they need to be proven to have performed the act in question with a “guilty mind;” that is, with knowledge of the wrongfulness of their behavior.

In situations when there is overwhelming evidence that the defendant performed the act, but was not in a state of mind to understand the full implications of what they were doing at the time of the crime, individuals may appropriately raise a state of mind defense. 


State of mind defenses get at the issue of criminal responsibility.  If a person performs an act but has no awareness of the legal wrongfulness of his or her behavior (or in some jurisdictions may know the legal wrongfulness, but not be able to appreciate the moral wrongfulness of the act), then this person may be found to have a diminished culpability for the crime.  Examples of state of mind defenses include extreme emotional disturbance and the not guilty by reason of insanity defense.

Insanity Defense Expert Witness

The insanity defense varies jurisdiction by jurisdiction and is not a national standard.  Not every state has an insanity defense and it is not a constitutional requirement in the United States that individuals be offered one.  Attorneys looking to defend clients with a legal defense for criminal responsibility may raise the insanity defense when there is a clear mental illness that interferes with an individual’s ability to distinguish right from wrong.  Take for example, an individual with a severe mental illness of psychotic proportions such as schizophrenia, and who commits a homicide due to a persistent persecutory delusional belief that the only way to save his or her family is by committing the homicide.  Depending on the case, there may be some evidence that the individual knew the legal wrongfulness of his or her behavior, yet based on the delusional belief, failed to appreciate the moral wrongfulness of the act.  In other words, this person may have felt morally justified in the killing.  This is an example of a case where a forensic psychiatrist could offer guidance and expertise in navigating through the question of sanity at the time of the crime.

Insanity Defense Psychiatrist

There are a variety of applications of criminal responsibility evaluations beyond the insanity defense.  In Colorado, for example, the state statute requires that examiners also consider whether a person possessed a culpable mental state (i.e. guilty mind) at the time of the crime, separate from the question of if they qualify for the insanity defense.

Either the prosecution or the defense may hire forensic psychiatrists.  In some states, the evaluations are court-ordered.  Irrespective of who the retaining party is, the goal of an evaluation by a well-trained forensic expert is to focus on striving for objectivity and arriving at an opinion the best approximates the facts as uncovered based on the evaluation performed.  In many cases, forensic experts on both sides of a given case will arrive at a similar opinion on the legal defense from criminal responsibility.

At Rocky Mountain Forensic Psychiatry, we are available to perform a variety of criminal responsibility evaluations for individuals charged with crimes, including extreme emotional disturbance and not guilty by reason of insanity (NGRI).  We also have significant experience working behind the scenes in a consultant role to a prosecuting state attorney on several insanity cases and have unique experience to offer attorneys with regard to consultation and consideration of key elements to be addressed in the case, including whether it is worth pursuing an insanity defense, or with regard to cross examination of opinions produced by other professionals.  For more information, please contact us.

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