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Helen M Farrell M.D.
Helen M Farrell M.D.
Law and Crime

Insanity Defense

Sanity hinges knowing right from wrong

What is insanity?

“Insanity is doing the same thing over and over again and expecting different results.”

- Albert Einstein

“In individuals, insanity is rare; but in groups, parties, nations and epochs, it is the rule.”

- Friedrich Nietzsche

Everyone from physicists to philosophers have a different opinion on insanity. Often equated to “craziness” or “madness,” insanity could be considered a spectrum of behaviors characterized by certain abnormal mental or behavioral patterns. Insanity is not a term that clinical psychiatrists use. In modern usage, it is most commonly encountered as an informal unscientific term denoting mental instability.

An affirmative defense, some criminal defendants claim insanity at the time of their crimes.

This is the case with Eddie Ray Routh, a troubled former Marine, accused of shooting the legendary Navy SEAL sniper Chris Kyle at a gun range in Texas. I have not evaluated Routh, but reports indicate that he will face life in prison without parole if convicted.

He and his lawyers hope to convince a jury that Routh was legally insane at the time of the act. This is not an easy feat.

The definition of legal insanity has evolved over time from the Wild Beast standard of the 18th Century … “a total deprivation of memory and understanding” to a more modern understanding that includes morality.

According to M’Naghten’s Rule, for a defendant to be found insane, it must be clearly provided that, “…at the time of the committing of the act, the party accused 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.’

The crux of the insanity defense is the issue of knowing right from wrong. There are numerous signs that forensic experts assess in reviewing cases like Routh’s and determining to a reasonable degree of certainty whether the defendant knew right from wrong. When defendants made an effort, for example, to avoid detection, they indicate that they knew right from wrong. Wearing gloves or a mask during the offense, concealing the weapon, falsifying information, or committing the act in the dark, are all tells that the person knew an act was bad. Disposal of evidence is another sign that the assailant knew right from wrong. This could involve anything from washing away blood to removing fingerprints to discarding the weapon. Another telling sign is making an effort to avoid apprehension such as fleeing the scene of the crime or lying to authorities.

I haven’t been involved in the American Sniper case, and I don’t have an opinion as to Routh’s mental state at the time of his actions. But I do know that Routh, as the defendant, has the burden of proving insanity.

Follow me on Twitter: https://twitter.com/HelenMFarrellMD

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About the Author
Helen M Farrell M.D.

Helen M. Farrell, M.D., is a psychiatrist with Harvard Medical School. She researches forensic psychiatry and violence.

Online:
TED bio, Twitter
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