Insanity Pleas in Pennsylvania

When it comes to criminal activity involving violent crimes, criminal defendants will often consider the factor of insanity in the process of committing the crime. However, insanity pleas in Pennsylvania can be confusing. It’s important to know the difference in determining insanity and mental illness as the overall sentencing will change.

Insanity Pleas and the M’Naghten Rule

When it comes to determining insanity in criminal proceedings, many Pennsylvania courts will review the M’Naghten Rule.

The M’Naghten Rule is the test that determines whether the accused was sane at the time of the crime and therefore, responsible for the criminal wrongdoing. Under this test, a defendant is found not guilty by reason of insanity if:

  1. At the time of the crime, he or she was so deranged that they did not know the severity of their actions, or 
  2. If the defendant did know the nature and quality of the actions but, at the time did not know to do so was wrong.

The purpose of the rule is to limit the insanity defense to only cognitive insanity. Cognitive insanity is the inability to distinguish right from wrong on the most basic level. In addition to the M’Naghten Rule, courts also utilize tests to determine if volitional insanity is to be a determinant. 

As defined by Legal Dictionary, “Volitional insanity is experienced by mentally healthy persons who, although they know what they are doing is wrong, are so mentally unbalanced at the time of the criminal act that they are unable to conform their actions to the law.”

In many jurisdictions across the United States, volitional insanity is questioned because of its fundamental leniency. 

The M’Naghten Rule has also been under scrutiny by the courts for a variety of reasons including:

  • Some defendants may meet the legal definition of insanity but do not reach medical criteria. So, when sentenced to mandatory medical care, it is not useful for recovery or understanding.
  • The rule does not distinguish which defendants may be a danger to the public or who isn’t if temporary or lifelong mental illness exists.
  • The test makes it too easy for a defendant with a severe mental disorder to escape responsibility, regardless of how much that diagnosis played in the crime itself.

Insanity vs. Mental Illness

Many individuals make the mistake of combining mental illness and insanity together when it comes to criminal proceedings. However, in Pennsylvania, these findings are very different when it comes to a sentence.

If someone is found guilty but mentally ill, the judge may believe that the person is guilty of the crime, but does not believe that the person was sane during the commission of it. The person will often be sentenced the same way as if it was a guilty verdict but it allows the court to determine the type of treatment needed for the mental illness.

The key difference is that insanity is a legal determination whereas guilty but mentally ill is medical. 

Insanity Pleas in Pennsylvania

Being accused of a violent crime can be a terrifying accusation, especially if you were not aware of t the actions you were committing or were unable to comprehend the situation. If you or a loved one is charged with a violent crime in Pennsylvania, you need a strong criminal defense attorney. Contact Mazzoni Karam Petorak & Valvano today for a free consultation.

Put your trust in a law firm that puts your best interests first. We offer a free case evaluation to all potential clients.

    Practice Areas

    Back to Top