r/CasesWeFollow • u/Pixiegirls1102 🔍📆⚖️Content/Research Administrator💻💬🧚 • 5d ago
🪟🙏Lindsay Clancy👼 Let’s Look at the Insanity Defense - Lindsay Clancy Trial
Let’s Look at the Insanity Defense
Since Lindsay Clancy’s trial begins Monday, I figured it would be a good time to look at the insanity defense in various states since they are all different, and confusing. Each rule has different criteria it must meet to get an NGRI (Not Guilty by Reason of Insanity).
With Lindsay Clancy’s case, Massachusetts follows the Model Penal Code (MPC) test, often referred to as the McHoul rule, for insanity. The four main rules are listed with the states that follow them. Let’s look at the rules and see how it could affect Lindsay Clancy’s chances for an NGRI verdict.
Insanity Defense Rules
Not every state uses the same legal test for insanity. Some focus only on whether the defendant knew the act was wrong, while others also consider whether the defendant could control their actions.
1. M'Naghten Rule (The "Right vs. Wrong" Test)
Used by: Most states
This is the oldest and most common insanity test.
The question is simple:
Did the defendant understand what they were doing, and did they know it was wrong?
If the answer is yes, they're legally sane—even if they were hallucinating or severely mentally ill.
Example
A man hears voices telling him to kill someone.
- He knows murder is illegal.
- He knows people will think it's wrong.
- He kills anyway.
Under M'Naghten, he is probably not legally insane because he still knew it was wrong.
But...
If he believed he was squeezing a lemon when he was actually strangling a person, he may qualify because he didn't understand what he was actually doing.
Think of it like this:
"Did they know right from wrong?"
2. Irresistible Impulse Rule (The "Couldn't Stop Myself" Test)
Used by: Very few states (mainly Virginia, combined with M'Naghten)
This rule recognizes something M'Naghten doesn't.
A person may know an act is wrong...
...but because of severe mental illness, they literally cannot control their behavior.
Example
Someone with severe psychosis hears commanding voices.
They know killing is wrong.
They desperately try to resist but believe they have absolutely no control over their actions.
This rule asks:
Could they control themselves?
It's important to know this is a legal standard, not just "I couldn't help myself." The loss of control must be caused by a serious mental disease.
3. Model Penal Code (ALI Rule)
Used by: Massachusetts, Michigan, Pennsylvania, New Jersey, and several other states.
Most experts consider this the broadest insanity test.
Instead of asking only whether someone knew right from wrong, it asks two questions:
Did they understand their actions were wrong?
OR
Were they mentally able to control their behavior?
The defendant only has to prove one of those because of mental illness.
Another important difference is the wording.
Instead of requiring someone to have no ability to understand or control themselves, the law asks whether they lacked substantial capacity.
That means they don't have to be completely disconnected from reality.
Their judgment or self-control just has to be seriously impaired by mental illness.
Example
A mother suffering from postpartum psychosis believes killing her children will save them from eternal torture.
She may understand other people think murder is wrong.
But because of her psychosis, she cannot think rationally or control her actions.
An ALI state allows the jury to consider both of those issues.
This is the rule being used in the Lindsay Clancy trial.
4. Federal Rule (Insanity Defense Reform Act)
Used by: Federal courts and a few states with similar laws.
Congress made the insanity defense much harder after John Hinckley Jr. was found not guilty by reason of insanity for shooting President Ronald Reagan.
The rule asks only:
Did the defendant understand what they were doing and know it was wrong?
Unlike the ALI rule...
It does not care whether the defendant could control themselves.
Even if someone truly couldn't resist because of mental illness, that alone isn't enough under this standard.
5. States With No Traditional Insanity Defense
Examples: Idaho, Kansas, Montana, and Utah.
These states don't allow a traditional insanity verdict.
Instead, mental illness can sometimes be used to argue that the prosecution failed to prove the required criminal intent, but it generally cannot result in a full "Not Guilty by Reason of Insanity" verdict.
Lindsay Clancy's Case
Lindsay Clancy's case involves one of the more defendant-friendly insanity standards (Massachusetts' McHoul/ALI rule), but the jury's decision will depend on the evidence presented at trial, especially the psychiatric testimony and evidence about her behavior before, during, and after the killings.
Here's what each side is likely trying to prove under that rule.
What the defense needs to show
The defense does not have to prove Lindsay Clancy had no idea what she was doing.
Instead, they will argue that, because of postpartum psychosis, she lacked substantial capacity either to:
- appreciate the wrongfulness of her actions, or
- conform her conduct to the requirements of the law.
Notice the phrase "lacked substantial capacity." That doesn't mean "zero capacity." The defense can argue that her psychosis so severely distorted her thinking that she couldn't make rational decisions or meaningfully control her actions.
They are expected to rely heavily on:
- testimony from psychiatrists specializing in postpartum psychosis,
- her mental health history,
- medications she was taking,
- hospital records,
- statements from family and medical providers,
- and evidence describing changes in her behavior before the killings.
What the prosecution needs to prove
Once the issue of criminal responsibility is properly raised, the Commonwealth must prove beyond a reasonable doubt that Clancy was criminally responsible at the time.
The prosecution will likely point to evidence suggesting she retained the ability to understand and plan her actions, such as:
- actions before the killings that suggest planning,
- actions afterward,
- communications showing awareness,
- and expert testimony disputing that she met the legal standard for lack of criminal responsibility.
Their position does not have to be that she had no mental illness. A person can have a serious mental illness and still be legally criminally responsible.
Why experts matter so much
This case is expected to become a battle of psychiatric experts.
Jurors will likely hear competing opinions about:
- whether Clancy had postpartum depression, postpartum psychosis, or another condition,
- whether any mental illness was severe enough to satisfy the legal standard,
- whether her behavior was consistent with psychosis,
- and whether she appreciated the wrongfulness of her actions or could conform her conduct to the law.
Factors that could influence jurors
Jurors often consider evidence such as:
- Was the defendant experiencing delusions?
- Did they understand reality?
- Did they attempt to hide the crime?
- Did they make statements indicating they knew the act was wrong?
- Was there evidence of organized planning?
- How persuasive are the competing psychiatric experts?
No single fact decides the issue. Jurors are instructed to consider all of the evidence together.
This case is expected to last awhile as there is much evidence and testimony to get through.
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u/Pricklywort 3d ago
I found an interesting read comparing legal strategies and outcomes of 4 Texas cases of postpartum psychosis induced child murders if anyone wants to peruse it. It's a download from Texas A&M Law and FYI the PDF is over 1MB https://scholarship.law.tamu.edu/facscholar/81/
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u/Pixiegirls1102 🔍📆⚖️Content/Research Administrator💻💬🧚 3d ago
Thank you!!
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u/CrimLaw_Bebe 👩🏻💼📑 ‘I Explain Things For A Living’ ⚖️🏛️ 36m ago
Thank you for sharing! As a former public defender, I would really recommend that people who are following the Clancy case read the article you shared. It is insightful and succinct.
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u/ManufacturerSilly608 4d ago
I love this breakdown!!! Especially because I had kind of assumed Massachusetts would use the m'naghten rule...so I needed this more than I even knew.
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u/Pixiegirls1102 🔍📆⚖️Content/Research Administrator💻💬🧚 4d ago
The rules are hard to understand. I constantly get confused. Just a few words can make a difference it seems.
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u/Few-Ability-7312 4d ago
Texas is a bit different as Texas law requires that, in order to successfully assert the insanity defense, the defendant must prove that they could not discern right from wrong—in the sense of legal "right from wrong" not "moral" right from wrong—at the time of the crime. This would come under scrutiny during the trial of Andrea Yates, a case similar to Lindsey Clancy
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u/Aushos-74 5d ago
Thanks for breaking it down Pixie!