Psychology in the Courtroom

Forensic Psychological Evaluation and Assessment: Psychology in the Courtroom

By Dr. David Dixon, Forensic Psychologist

Forensic psychology is a clinical psychology specialty which intertwines the law with two types of professional services: (1) psychological evaluation and assessment to assist the defense or prosecution of criminal cases or civil commitment proceedings; and (2) “rehabilitation” of criminals once in the prison system.

When a person is charged with a misdemeanor or a felony, their mental state or mental illness may be an issue to consider before conviction or before sentencing.  The attorney representing the accused person may request a psychological evaluation.  Sometimes a psych evaluation is court ordered.

The state (prosecution) carries the burden of proving “beyond a reasonable doubt” that the defendant “formed the requisite mens rea to commit the crime.”  [A "reasonable doubt" is a doubt based on reason and common sense after a careful and impartial consideration of all the evidence in the case.  It is a kind of doubt that would make a reasonable person hesitate to act in the most important of his/her own affairs.  "Mens rea" is Latin for "guilty mind." It is a criminal law concept, which focuses on the mental state of the accused. Did the person know that the act or omission was illegal or prohibited?]

Forensic Evaluation & Assessment

When the court appoints a psychologist or psychiatrist as an expert witness, the psychologist or psychiatrist examines the defendant (patient).  A determination is made as to whether there is substantial evidence that the patient suffers a mental disorder.  Emotions such as fear, jealousy, anger or hatred are not considered a mental disorder.

The psychologist or psychiatrist needs to consider psychological influences at the scene of the alleged crime (for example, provocative social situations, injury, physical illness, medical neurological diseases, adverse environmental conditions, etc.).  Depending on the outcome of the examination, the psychologist or psychiatrist may testify in court how the impaired mental abilities “actually caused a malformation of the mental element of the crime.”  An expert opinion is rendered regarding whether the “mental element probably failed to be formed.”

The expert does not have to be certain that the defendant’s disorder caused him or her to be unable to form the intent or “knowledge,” but the expert must have some belief in the “probability or possibility” that it did.  Experts need to testify with “reasonable” medical and psychological certainty.

The old “insanity defense” or “M’Naughten” test was: “At the time of the commission of the offense, as a result of a mental disease or defect, the mind of the actor was affected to such an extent that: (1.) He was unable to perceive the nature and quality of the act with which he is charged; or (2.) he was unable to tell the difference between right and wrong with reference to the act charged.”

WPIC 20.01 INSANITY AT THE TIME OF OFFENSE–DEFINITION (Judges’ instructions to the jury.)

In addition to the plea of not guilty, the defendant has entered a plea of insanity existing at the time of the act charged.

Insanity existing at the time of the commission of the act charged is a defense.

For a defendant to be found not guilty by reason of insanity you must find that, as a result of mental disease or defect, the defendant’s mind was affected to such an extent that the defendant was unable to perceive the nature and quality of the acts with which the defendant is charged or was unable to tell right from wrong with reference to the particular acts with which the defendant is charged.

Diminished Capacity, Competency and Mitigating Circumstances

The law defines three main areas of defense related to mental health: (a.) Diminished capacity, (b.) Competency, or (c.)  Mitigating circumstances.

A diminished capacity evaluation focuses on whether or not a person was able to “form the specific, or “requisite intent’ (or “know”) to commit the alleged crime.  The expert witness would comment as to whether the individual, in his/her opinion, was organized, purposeful, and goal oriented/directed.  The major question is, was the behavior affected by a mental disorder of mood or thought?  At that time, was this underlying disorder exacerbated by alcohol and/or drug intoxication?  An “irresistible impulse” is one induced by a mental disease affecting the volatile powers so that the person afflicted is unable to resist the impulse to commit the act that he/she has been charged with.

Criminal Law — Diminished Capacity  — Instruction — Necessity

The issue of a criminal defendant’s alleged diminished capacity is considered by the trier of the fact only is there is substantial evidence that the defendant has a mental condition and the evidence reasonably connects the alleged mental condition with the inability to possess the required level of culpability to commit the charged crime.

A competency evaluation assesses whether a person has the mental facility or ability to understand the legal proceedings against them.  In addition, the evaluation focuses on determining whether they are able to assist their attorney in their own defense.

Mitigating circumstances are sometimes considered regarding the defendant’s capacity to “appreciate the wrongfulness of their conduct or to conform his conduct to the requirements of the law.”  In this legal exception, voluntary use of alcohol or drugs is excluded.  The plea of mitigating circumstances is used primarily in consideration at sentencing.

WPIC 18.10 VOLUNTARY INTOXICATION (Judges’ instructions to the jury.)

No act committed by a person while in a state of voluntary intoxication is less criminal by reason of that condition.  However, evidence of intoxication may be considered in determining whether the defendant [acted] [or] [failed to act] with (fill in requisite state).

NOTE ON USE: Use this instruction for voluntary intoxication cases only.  It does not apply to a case in which involuntary intoxication is claimed.

The forensic assessment looks at many psychiatric diseases and personality disorders and diseases, which may cause problems with intellectual functioning and memory.  These include general assessment of brain damage caused by head injury, deteriorative brain diseases, and acute chronic alcohol and drug abuse to specific requests for evaluation such as “determination of methamphetamine addiction and violence, brain damage or dementia resulting from methamphetamine use.”   At times, the forensic examination includes a battery of psychological tests called neuropsychological testing.

Expert Witness Testimony

The psychiatrist or psychologist who is asked to prepare a forensic psych evaluation (to examine and evaluate a patient in anticipation of prosecution or litigation) may be recognized by the court to serve as an expert witness. An expert witness–by virtue of education, profession, and experience–is considered to have special knowledge of the subject beyond that of the average person, sufficient that others may legally and officially rely his opinion.

The psychiatrist or psychologist serving as an expert witness may give professional opinions in court about matters that are relevant to his or her expertise.  By contrast, other (non-expert) witnesses usually can only testify about the facts in the case and are not permitted to include their opinions in court testimony.

Expert witnesses are not paid for their testimony.  However, like attorneys and other professionals, they are paid for their time and expertise.  Expert witness testimony may also be used in a personal injury case when the plaintiff makes a case that they suffered undue pain and suffering in a mental or emotional manner.

Expert witnesses must present their credentials and training accurately.  They are subject to cross examination and attacks on their reputation, credibility and opinions.  Expert witnesses must be careful to avoid taking these attacks personally and becoming angry.  Loosing their temper may be exactly what opposing counsel wants them to do.  Court proceedings are usually an adversarial process.  The expert witness must remember that the cross-examining prosecutor or attorney is just doing his/her job.