How Mental Illness and Insanity Differ in Criminal Cases

February 26, 2019

How Mental Illness and Insanity Differ in Criminal Cases

Did you know? When it comes it criminal charges, your mental health may matter to your criminal defense. However, you should also realize the difference between mental illness and insanity. Could either be relevant to your case?

For starters, you might want to take a look at how 18 PA Cons Stat § 314 distinguishes mental illness from legal insanity. Notably, the definitions apply in two aspects of criminal cases. The first concerns consideration of either a defense or a guilty plea of either. Secondly, the courts use the same definitions in determining sentencing.  Broken down:

  • “Mentally ill.” – One who as a result of mental disease or defect, lacks substantial capacity either to appreciate the wrongfulness of his conduct or to conform his conduct to the requirements of the law.
  • “Legal insanity.” At the time of the commission of the act, the defendant was laboring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing or, if he did know it, that he did not know he was doing what was wrong.

M’Naghten Rule: Criminal Insanity

The statute also includes a reference to the M’Naghten Rule, a test for criminal insanity. Its origins date back to 1843 and English law.

More specifically, Daniel M’Naghten attempted to kill the then prime minister and inadvertently shot his secretary instead. The defendant thought the prime minister was out to get him.

Ultimately, the court found M’Nagthen not guilty by reason of insanity. This occurred after expert witnesses testified that the defendant was psychotic. Under Pennsylvania law, medical professionals could find you mentally ill – but that doesn’t mean you are legally insane.

Despite what you might have seen on television, insanity defenses are the exception rather than something asserted regularly. The standard of proof differs from the balance of the criminal case. Your attorneys must prove insanity by a preponderance of the evidence.

Understandably, the difference between mental illness and insanity might still confuse you. For the most part, you’ll most often see the defenses raised if you’re accused of a more serious felony crime.  These would include accusations of murder and manslaughter, as well as a number of sex crimes.

Meanwhile, the possibility remains that you can be found guilty but mentally ill. This gives the court some discretion concerning sentencing guidelines.

Mental Illness and Sentencing

More than a decade ago, the National Alliance on Mental Illness (NAMI) came out with a frightening characterization. According to a report they gave,  today’s “jails and prisons are emerging as the “psychiatric hospitals” of the 1990s.” You may worry about this first hand if you or a loved one suffers from severe mental illness such as schizophrenia or bipolar disorder.

Pennsylvania law recognizes the significance of mental illness when it comes to the disposition of defendants who are found guilty but mentally ill. According to 42 PA Cons Stat § 9727, the judge may mirror sentencing for other defendants whose plea or conviction does not include mental illness.

However, there is good news. In sentencing defendants who are severely mentally disabled, the court may also order psychiatric or psychological treatment. In some cases, this may be provided within prison. In others, the offender could be transferred to a mental health facility.

Contact Us

Statistical research shows that forty percent of people suffering from mental illness are arrested for crimes. Truth be told, this includes an array of people. In some cases, a drug offender might commit a serious crime to support a habit. In many cases, drug offenders have significant dual diagnoses regarding mental health issues.

At Mazzoni Karam Petorak & Valvano, we recognize that mental illness may be a factor in your criminal defense. Contact our offices to set up a meeting to discuss your case. Let us help you or your loved one with experienced legal advice.

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