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  • Writer's pictureJustin Sparks

What Insanity Test Is Used in Texas? A Comprehensive Guide

The insanity defense has actually been part of criminal law in America since the 1700s. The earliest tests for excusable insanity focused on whether the defendant had a similar mental capacity to a wild beast. However, the concept has since evolved, and the tests states use vary significantly.

It's crucial to look at the insanity defense in the larger scope of how it pertains to criminal law.

Overall, the state's responsible for making sure criminals are held liable and accountable for their actions. To do that, the state has to prove several elements of the crime beyond a reasonable doubt.

Among those is mens rea, which translates to a "guilty mind." It must show that the accused had some sort of criminal intent and must have been cognizant enough to know they did wrong and that his or her conduct was a crime.

When the prosecution has carried the burden and shown this, the defendant can present their defense. In most cases, the first response focuses on indicating that the prosecution hasn't met the burden of proof.

However, when the prosecution does meet its burden, there are only two possible defenses the defendant can use. Both submit that the defendant is not guilty, despite the prosecution's case:

  • The first defense option is "justification." This can include self-defense and more.

  • However, the second defense option is "excuse." Overall, the insanity defense is one example of this.

Regardless, the defendant is arguing and telling the jury that even if the prosecution has carried the burden and proved that they did it, there must be a not-guilty sentence because the actions were somehow justified or they had an excuse for doing it.

The Tests Used to Determine Severe Mental Disease or Sanity in a Criminal Trial

The Tests Used to Determine Severe Mental Disease or Sanity in a Criminal Trial

Each state's laws govern the required elements to use the insanity defense, and there's absolutely no uniformity among them. Four states refuse to allow an insanity defense at all. All other states offer four forms of the insanity defense.

The four tests each require two elements. Therefore, the accused must have already been diagnosed with schizophrenia, paranoia, mental retardation, or any other mental illness. However, the second element will vary. Let's look at them now:

  • The Irresistible Impulse Test - This indicates that the accused person's mental illness denied them the ability to restrain their impulses, ultimately committing the crime even though they knew it was wrong to do so.

  • The M'Naghten Defense - This is commonly called the "right or wrong" test. In a nutshell, the accused didn't know the differences between wrong and right at the time, but it's often more complicated than this. Overall, the jury will have to find that the person's mental illness resulted in them being unable to know the quality or nature of the criminal act or that it was wrong.

  • The Durham Insanity Defense - This is only available in New Hampshire and states that the accused isn't responsible for the crime if the mental illness caused them to do it.

  • The Substantial Capacity Test - This says the accused isn't responsible for the crime if the mental illness caused a lowered capacity to understand the conduct was criminal. Likewise, they could not conform the conduct they used to the legal requirements of society.

Differences Between Diminished Capacity and Full Affirmative Defense (Insanity Defense)

Typically, insanity defenses are called "excuse" defenses. They ultimately admit that the prosecution showed enough evidence to convict the person, but their insanity excused the defendant's action. Therefore, the jury must reject the guilty verdict because of this.

On the other hand, diminished capacity is considered a partial affirmative defense. It plays off the mens rea element, which is essential to the prosecution's case. To satisfy this element (mens rea), the prosecution is required to show that the accused person had a criminal intent to commit the crime they're charged with.

For example, the prosecutors charge the defendant with first-degree murder. Therefore, they must show that the accused person wanted to commit the elements that led to a first-degree murder.

What's Mens Rea Mean?

Many people have never heard of mens rea and don't know what it means. This is a Latin term that indicates "guilty mind." Overall, it's the legal concept that distinguishes between someone who intentionally set out to commit a crime and one who did not mean to do so.

Here's a simpler breakdown: The mens rea element of the crime refers to the intention or the mindset of the person who committed it. It focuses on what they were thinking at the time of the offense.

For example, someone knocks over a shop vase, and it is an accident. They don't have the mens rea element for a crime being committed because they didn't mean to damage the property. However, if they smashed the vase deliberately or on purpose, they had the mens rea element because they wanted to cause damage and ultimately did so.

Using a diminished capacity defense will argue that the accused person didn't have the mental capacity necessary to have the criminal intent (mens rea) to commit the crime. Therefore, they might be charged with lesser crimes or nothing at all.

Competent Enough to Stand Trial

The insanity defense and competency to stand trial are often confused.

With an insanity defense, it's a legal strategy arguing that the defendant cannot be held responsible for their actions, even if it was a criminal procedure. Overall, they weren't mentally capable of realizing the conduct's wrongfulness at the time they committed the crime.

Competent enough to stand trial focuses on the defendant's ability to understand the charges, what will happen at the trial, and their rights. If they're not competent enough to stand trial, the criminal proceedings are postponed. Professionals will treat them until they are competent, and the jury trial will then resume.

Proving Insanity (Severe Mental Illness) in Criminal Trials

While this wasn't always the case, today, every state puts the burden of proof on the defendant, which includes the insanity defense. However, it's different than the prosecution's burden because the defense must only prove insanity by what the evidence shows, which is standard in civil cases.

To prove the insanity defense, the accused has to have been diagnosed with severe mental illness or defect first, which can include mental retardation, schizophrenia, or paranoia. Then, the defense will ask to have an expert perform a psychiatric evaluation. In most cases, the defense is required to give notice of the intent to plead insanity and mental health problems 21 days before the trial.

After the evaluation, the jury or judge determines if the accused was properly diagnosed with a mental health condition. Likewise, they must focus on if the diagnosis led to the second element of the insanity test applied.

The Insanity Test Texas Uses

Texas Penal Code 8.01 claims that insanity is the affirmative defense to the prosecution that, when the conduct was charged, the actor didn't know it was wrong because of a severe mental disease or defect. Wrong and illegal are the same terms here.

In a sense, this is the M'Naghten test, which requires a causal connection between the mental disease and the absence of the person's cognitive awareness for the legality of their actions. Sparks Law Firm can give insight to questions like What is the M'Naghten rule in Texas?

Why People Are Critical of This Insanity Defense Option?

There are varying critical views out there of insanity defenses, which happens from the disparity among the tests. Likewise, policies have evolved within different states, which results in an inconsistency for applying justice.

Some people claim that guilty defendants will fake insanity to get a lighter sentence or get acquitted of the crime. However, a report from the Washington Post claimed that, in 1990, eight states saw fewer than one percent of all defendants using the insanity defense as a plea.

Finally, the four insanity tests require a mental illness to be the causal link for the criminal conduct. Still, there are inconsistencies in what qualifies as a mental defect or illness.

What Might Happen to the Defendant When They're Acquitted of Violent Crimes Because of Insanity?

A defendant doesn't go free if they're guilty by reason of insanity. Though they're not incarcerated at a prison, they're held in a state mental hospital until a doctor says their sanity has been restored. Overall, this means that the patient isn't a danger to others or themselves.

Sometimes, mental patients who are found to be not guilty by reason of insanity spend more time in a mental hospital than they would have in prison if they'd been found guilty of the crime.

In some situations, the person doesn't go to a mental hospital. They might be ordered to do an outpatient or community-based treatment or be placed in a residential care facility for a period of time. However, that period can't exceed the maximum period determined by law for the offense.

When the maximum term expires, the offender can only be confined to the court-ordered program or treatment under civil commitment proceedings.

Famous Cases Using the Insanity Defense

Famous Cases Using the Insanity Defense

There have been many famous cases where criminal defense attorneys in Fort Worth argued and won the insanity defense plea for clients. Here are three of the top ones:


John Hinkley was ultimately not guilty by reason of insanity in 1982 for attempting to assassinate President Ronald Reagan. However, the verdict was greeted with calls for reform and pure outrage over the criminal justice system. At the time, insanity pleas because of mental health problems were only part of two percent of all felony cases, and over 75 percent of them failed.

Regardless, many states adopted significant changes because of public pressure.

Lorena Bobbitt

There's also the Lorena Bobbitt case, where she was considered not guilty by reason of insanity in 1993 after she cut off her spouse's penis. He'd raped her while drunk, and she ran from the home and drove away without knowing what she'd done. Later, she'd driven for a while and realized she was still holding the severed penis and kitchen knife in her hands. She then threw the penis out the window, keeping the knife.

The jury claimed she wasn't guilty by reason of insanity (temporary). Virginia has no statutory definition for the insanity defense, and the test is defined by whatever common laws there are.

Each of the common law tests requires a mental illness diagnosis. However, Lorena wasn't diagnosed previously, so one can only assume that the mental illness or defect was temporarily found at the time of the crime.

Andrea Yates Case

A Texas jury found Andrea Yates not guilty by reason of insanity in 2001 for drowning her five children. She thought by doing so, she would save them from Satan.

Overall, she was diagnosed with various mental disorders, including schizophrenia.

Texas uses the M'Naghten test for insanity defenses. Therefore, the jury found that her mental illness caused the irrationality in believing that she was doing something good and saving her kids from Satan.

Call a Criminal Defense Attorney in Ft. Worth, Texas

Being accused of a crime is a scary situation, and it's crucial to work with a seasoned criminal defense attorney who understands criminal law. They can devise an appropriate legal defense and gather evidence to cast doubt on the prosecutor's evidence.

A criminal conviction can have serious consequences, such as jail time and fines. Therefore, it's crucial to protect one's rights by speaking to a lawyer like the one at Sparks Law Firm.

If there are mental health issues, one of the lawyers here might use the reason of insanity defense, though there are other options available. The laws are quite complicated, and potential clients require someone who will fight for them.

When facing criminal charges, one needs the top attorney, and Sparks Law Firm is here to assist those living in Ft. Worth, Texas. Please request a free consultation. One might also use the contact form to get a consultation. Regardless, it's crucial to work quickly and get the assistance necessary to deal with the case.


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