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    Not guilty by reason of insanity. Understand when and how the insanity defense can be argued in criminal cases.

    not guilty by reason of insanity

    The insanity defense has been a part of American criminal defense since the early 1700s in the English colonies. The early test for excusable insanity was whether the defendant had no more mental capacity than a wild beast. Since then, the concept has evolved so that today the tests vary among the states.

    It’s important to examine the insanity defense in the larger scope of criminal law. 

    The state is responsible for holding criminals accountable. In order to do this, the state must prove, beyond a reasonable doubt, several elements of the crime.

    Among those elements is mens rea, literally translated as “guilty mind.” It requires that the accused had criminal intent. The accused must be cognizant that they are doing the wrong thing and that their conduct is a crime.

    Once the prosecution has carried its burden, the defendant has the opportunity to present their defense. 

    Their first response is to show that the prosecution has not met their burden. 

    In cases where the prosecution has met its burden, there are 2 possible defenses that can be used, both of which submit that, despite the prosecution’s case, the defendant is not guilty:

    • The first kind of defense is the “justification” defense. Self-defense is an example of the justification defense.
    • The second kind of defense is the “excuse” defense. The insanity defense is an example of the excuse defense.

    In both kinds, the defendant is arguing to the jury that, even if you assume the prosecution has carried its burden (i.e., I did it), you must find me not guilty because my actions were justified, or I had a legitimate excuse.

    What are the rights of a defendant?

    When a defendant stands trial, he has several inalienable rights that are guaranteed to him through the U.S. Constitution.

    What tests are used to determine sanity in a criminal trial?

    State law governs the required elements of an insanity defense. There is no uniformity among the states. Four states disallow any form of the insanity defense. Among the other states, there are 4 different forms of the insanity defense.

    All 4 tests require 2 elements. Each form requires that the accused must be diagnosed with a mental illness, such as paranoia or schizophrenia. The 2nd element varies among the states.

    • The M’Naghten defense is commonly known as the “right or wrong” test, where the accused does not know the difference between right and wrong, although it’s a bit more complicated than that. The jury must find that the accused’s mental illness caused them to be unable to know either the nature and quality of their criminal act or that the act was wrong.
    • The irresistible impulse defense is that the accused’s mental illness denied them the will to restrain the impulse to commit the crime even if they knew it was wrong.
    • The substantial capacity test is that the accused is not responsible for their crime if their mental illness causes them to lack substantial capacity either to understand that their conduct is criminal or conform their conduct to legal requirements.
    • The Durham insanity defense is available only in New Hampshire. It is that the accused is not responsible for their crime if their mental illness caused them to commit it.

    What’s the difference between insanity and diminished capacity?

    Insanity defenses are “excuse” defenses that effectively admit that the prosecution meets its burden to convict but that insanity excuses the accused’s action and rejects a guilty verdict.

    Diminished capacity pleading is a partial affirmative defense that plays off of the mens rea element that is essential for the prosecution’s case. To satisfy the mens rea element, the prosecution must show that the accused had the criminal intent to commit the crime for which they are charged. If the prosecution charges them with 1st-degree murder, they must prove the accused intended to commit all of the elements of 1st-degree murder.

    Key terms in criminal justice: Mens Rea

    “Mens rea” is a Latin term meaning “guilty mind.” It’s a legal concept distinguishing between someone who did not mean to commit a crime and someone who intentionally set out to do so.

    In simpler terms, the “mens rea element” of a crime refers to the mindset or intention of the person who committed the crime. It’s about what was going on in their head at the time. 

    For example, if someone accidentally knocked over a vase in a shop, they wouldn’t usually have the mens rea for a crime because they didn’t mean to do it. 

    But if they deliberately smashed the vase, they would have the mens rea because they intended to cause the damage.

    A diminished capacity defense argues that the accused did not have the required mental capacity to have the mens rea (criminal intent) to commit 1st-degree murder. The accused is claiming that they can only be charged with a lesser crime.

    Competency to stand trial

    Competency to stand trial is often confused with an insanity defense. 

    An insanity defense is a legal strategy used to argue that the defendant shouldn’t be held criminally responsible for their actions because they were not mentally capable of understanding the wrongfulness of their conduct at the time the crime was committed.

    Competency to stand trial pertains to the defendant’s ability to comprehend the charges against them, their rights, and what is going on at trial. If they are determined to be not competent to stand trial, the proceedings will be postponed while professionals treat them to restore their competency. If it is restored, the trial will resume.

    How do you prove insanity in a criminal trial?

    Although it was not always the case in all states, today, in every state, the defendant has the burden to prove the insanity defense. However, unlike the prosecution’s burden, the defense only has to prove insanity by a preponderance of the evidence, which is the standard for most civil cases.

    To successfully prove an insanity defense, the accused must first be diagnosed with a mental illness or defect. The defense must ask for a psychiatric evaluation by an expert who is assigned to the defense. The defense must give notice of their intent to plead insanity at least 21 days before trial.

    Based on the evaluation, the judge or jury will decide whether the accused is properly diagnosed with a mental illness or defect. The jury must also determine whether the diagnosed mental illness caused the second element of whatever insanity test is applied.

    Which insanity test is used in Texas?

    Texas Penal Code §8.01. provides that insanity “ is an affirmative defense to prosecution that, at the time of the conduct charged, the actor, as a result of severe mental disease or defect, did not know that his conduct was wrong.” For this purpose, “wrong” is interpreted as “illegal.”

    This is essentially the M’Naghten test, requiring a causal connection between a mental disease and the absence of a cognitive awareness of the illegality of the accused’s actions.

    Why are people often critical of the insanity defense?

    A major reason for critical views of insanity defenses is the disparity among states’ insanity tests. Also, the evolution of policies within individual states has resulted in inconsistent application of justice within the states.

    Some critics argue that some guilty defendants fake insanity to be acquitted or get a lighter sentence. However, it’s reported by the Washington Post that, in 8 states in the 1990s, less than 1% of defendants pleaded the insanity defense.

    Finally, in each of the 4 insanity tests, there must be a mental illness that has a causal link with the criminal conduct. But there is inconsistency in the definitions of the qualifying mental illness or defect.

    What happens to a defendant if they’re acquitted of a violent crime due to insanity?

    A defendant does not go free if they are not guilty by reason of insanity. While they will not be incarcerated in a prison, they will be held in a state mental hospital until such time that a doctor determines their sanity is restored. A fundamental determination is that the patient is no longer a danger to themself or others.

    Sometimes, a mental patient, who is found to be not guilty by reason of insanity, will spend more time locked up in a mental hospital than they would have spent in prison if they had been found guilty of their crime.

    Famous insanity defense cases

    Below are some examples of famous cases in which criminal defense attorneys were able to successfully argue the insanity defense for their clients.

    The Lorena Bobbitt case

    In 1993, a Virginia jury found that Lorena Bobbitt was not guilty by reason of insanity for cutting off her husband’s penis. He had just raped her when he was drunk. After the event, she ran out of her home and drove off without awareness of what she had done. She later realized, only after driving for a while, that she held her kitchen knife in one hand and his severed penis in the other, at which time she threw the penis out of the window and kept the knife.

    The jury held that she was not guilty by reason of temporary insanity.

    Virginia does not have a statutory definition of an insanity defense. The Virginia test is defined by common law.

    Each of Virginia’s common law tests requires a diagnosis of a mental illness. Lorena Bobbitt was not diagnosed as having a previous mental illness or defect. We can only assume that a causal mental illness or defect was found to be temporarily existing at the time of the crime.

    The temporary insanity defense is sometimes regarded as a rebuttal to the prosecutor’s evidence of mens rea.

    The Hinkley-Reagan case

    In 1982, John Hinkley was found not guilty by reason of insanity for the attempted assassination of President Ronald Reagan. The verdict was greeted with outrage and calls for radical reform of the criminal justice system. However, at the time, insanity pleas were entered in only 2% of felony cases and more than 75% of those pleas failed.

    Nevertheless, significant changes were adopted in many states in response to the public pressure.

    The Andrea Yates case

    In 2001, a Texas jury found that Andrea Yates was not guilty by reason of insanity for drowning her 5 children, believing she was saving them from Satan.

    She was diagnosed with schizophrenia and other mental disorders.

    Texas applies the M’Naghten test for the insanity defense. The jury found that Andrea’s mental illness caused her to irrationally believe that she was doing good, not bad, by saving her children from Satan.

    Contact a Houston criminal defense attorney

    If you or a loved one has been accused of a crime, it’s vital that you seek help from a skilled criminal defense attorney. An attorney can gather evidence and devise a legal defense that casts doubt on the prosecution’s evidence against you. Being convicted of a crime can have serious consequences beyond fines and jail time, so protect your rights today by talking to a lawyer about your case.

    If you live in the Houston area, contact an experienced criminal defense attorney at The Law Office of Matthew D. Sharp to ensure your rights are protected. Matthew D. Sharp is a seasoned criminal defense attorney who is committed to ensuring that those accused of criminal offenses get treated fairly and receive the best possible outcomes in their cases.

    Contact The Law Office of Matthew D. Sharp today for your free consultation.