Essay: Legal insanity

Forensic psychologists are faced with many laws, guidelines, and legal standards when providing an assessment regarding a legal insanity defense.

There are many facets that must be considered and or met prior to making a final conclusion relating to a defendant and the insanity diagnosis. It is important to form an analysis of what factors led up to the commission of the crime which will involve reports and statements from eye witnesses, investigative facts gathered by the police, autopsy reports, and tests results performed in crime labs. There must be a focus regarding whether or not the defendant understands his or her wrongful behavior in committing the crime he or she is accused of. The forensic psychologist must supply the courts with factual and empirical proof which meet the requirements of the court and legal system to prove legal insanity.

Case History

The defendant is a 45 year old male with a felony history and a confirmed diagnosis of paranoid schizophrenia. He has received mental health care for his diagnosis but it is not clear if the care continues. He was recently released from prison after fifteen years of incarceration for arson which led to the death of his stepfather. The defendant believed his stepfather was poisoning his mother prior to committing arson. When he set the home on fire he knew that there was no way the stepfather would be able to escape because of his disability.

The defendant is now facing charge of bank robbery. He waited in line and presented a note to a teller demanding money in the name of Jesus and when it was placed on the counter he turned and walked away without taking the money. He was arrested shortly after the attempted robbery. He told the police he was a king and had been waiting for a few days for several hundred million dollars and 250 virgin wives during the interview he exhibited a rambling incoherent conversation at times. He appeared to be homeless due to his dirty clothing and poor body hygiene. The defendant appeared cooperative, understanding of his legal rights and what the judicial system would be doing. Once the defendant was booked on charges of bank robbery he diagnosis of paranoid schizophrenia was confirmed and was given anti-psychotic medication.

Assessment Instruments

One of the instruments commonly used in the assessment and diagnosis of insanity is the Roger’s Criminal Assessment Scales or R-CRAS (Rogers, Seman, & Wasyliw, 1983). This assessment tool is empirically based and provides for determining impairment during the commission of the crime. R-CRAS meets the legal standard for use by an expert witness or forensic psychologist (Rogers, Seman, & Wasyliw, 1983). This assessment tool helps in establishing a mental impairment based on psychological variables which are necessary in the effort to diagnosis an individual as insane. Another component of this tool assists in providing an accurate opinion under the ALI standard for criminal responsibility and experimental models based on the M’Naghten standards regarding guilty but mentally ill (Rogers, Seman, & Wasyliw,1983). The ALI standard was designed with the intent of making the M’Naghten standard less rigid. Thee ALI standard states ‘a person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality of his conduct or to conform his conduct to the requirements of the law’ (Inderbitzin, 1969). Studies related to the R-CRAS have proven to be an extremely reliable assessment instrument producing high reliability and level of accuracy in determining whether an individual is insane or sane. The R-CRAS is commonly used by psychologists in determining psychosis as well.

The second assessment instrument used in determining legal insanity is the MSE or Mental Status Exam. Phillipe Pinel, a well know physician, stated “to seize the true character of mental derangement in a given case, and to pronounce an infallible prognosis of the event is often a task particular delicacy and requires the united exertion of great discernment of extensive knowledge and of incorruptible integrity” (The Mental Status Examination, 2013). The composition of the MSE involves three interviews with one focusing on the defendant’s personal and family history. The information is vital in understanding the defendant’s psychological status while committing the crime. It is extremely important to be observant of the defendant’s body language involving, speech, eye contact also the physical appearance and hygiene. The defendant’s psychological status before and after the crime are crucial (PsychWest, n.d.). Once all the information is collected from the interviews regarding strange behavior or any suspected mental health issues the psychologists can begin to evaluate and rate the information. Behavior and history is not the only items evaluated for the final diagnosis and report there are other sources of information regarding police reports, defendant’s report of what happened as well as any attorney reports must be considered as well. The MSE and R-CRAS are claimed to be the only two assessment tools for the use of evaluation in determining insanity (Grisso, 2003). Each of these two assessment tools are used for diagnosing psychosis.

The history regarding the defendant, his behavior in the past and present along with his diagnosis of paranoid schizophrenia I believe that he is insane and should be adjudicated as such. His behavior indicates serious mental deficiencies although during his interview with the psychologist he appears rational. The behavior he exhibits with the psychologist during the interview is a result of the anti-psychotic medication the defendant has been taking which is promoting some level of rationality.

Source: Essay UK -

Not what you're looking for?

Search our thousands of essays:


About this resource

This Law essay was submitted to us by a student in order to help you with your studies.

Word count:

This page has approximately words.



If you use part of this page in your own work, you need to provide a citation, as follows:

Essay UK, Essay: Legal insanity. Available from: <> [24-01-19].

More information:

If you are the original author of this content and no longer wish to have it published on our website then please click on the link below to request removal:

Essay and dissertation help

Latest essays in this category:

Our free essays:


GENIE 580XCD Aktenvernichter Cross Cut Partikelschnitt Papier Schredder Shredder | Order History | 1x896 Acacias 38