7 Notorious Defendants Who Successfully Used The Insanity Defense

The case began when Roosevelt decided to run for his third term in office.

Schrank shot the former president while he was campaigning in Milwaukee, Wisc., according to the Smithsonian. The bullet hit Roosevelt in the chest.

Schrank later told police former President William McKinley appeared in a dream and said he had been assassinated by Roosevelt.

"I looked upon his plan to start a third party as a danger to the country; my knowledge of history, gained through much reading, convinced me that Colonel Roosevelt was engaged in a dangerous undertaking," Schrank told police, according to the Smithsonian. "I was convinced that if he was defeated at the Fall election he would again cry ‘Thief’ and that his action would plunge the country into a bloody civil war.”

Doctors eventually declared Schrank insane, and a judge sentenced him to life in an asylum, according to PBS.

Bobbitt chopped off her husband's penis and tossed it out the car window while driving along a Virginia highway.

She said she did so because her husband, John Wayne Bobbitt, emotionally, physically, and sexually abused her during their marriage, according to The Los Angeles Times, which covered her acquittal in 1994.

She also claimed her husband raped her on the night she cut off his penis.

Jurors acquitted Lorena Bobbitt of the crime, agreeing with the defense that she suffered an "irresistible impulse" caused by the abuse, the Times reported.

Bobbitt was ultimately committed to a mental hospital. However, the judge ordered her released from the hospital five weeks after her acquittal, according to the LA Times.

Pound allegedly received money from the Italian government during World War II to create pro-Fascist radio broadcasts.

He went on anti-American and anti-Semitic rants all the while idolizing Hitler and Mussolini and calling President Roosevelt "that Jew in the White House," according to PBS.

Pound was extradited to the U.S. following Mussolini's death where he was ultimately declared unfit for trial. He was committed to St. Elizabeth's Hospital, an asylum, for 12 years.

However, that decision later sparked some controversy years after the fact, with historians and psychiatrists alike questioning whether Pound was actually insane.

Professor Stanley Kutler told The New York Times back in 1981 that Pound was "eccentric" but not insane.

"The judgment of the doctors was that he had personality-trait disturbance and a narcissistic personality - but that is not a psychiatric judgment," Kutler told the Times. "Nobody ever actually said he was insane. He himself chose to plead that way."

Hinckley claimed he was just trying to impress Jodie Foster when he shot shot Reagan, a secret service agent, a Washington police officer, and Reagan's press secretary, according to PBS.

A jury ultimately acquitted him of 13 charges, believing he was legally insane, according to an article by University of Missouri, Kansas City School of Law professor Doug Linder.

Public outcry over the verdict spawned a number of changes in the ways courts weigh insanity defenses.

Senator Arlen Specter proposed shifting the burden of proof of insanity over to the defense, a measure supported by Reagan and a majority of states, Linder wrote.

Within three years of the verdict, two-thirds of states adopted some variation Specter's proposal and required the defense to be the ones to prove insanity.

Lee Robin killed his wife with an ax and drowned their nearly-3-month-old daughter in 1988, The Chicago Tribune reported at the time.

But instead of running from police, the Palatine, Ill.-based doctor waited at the family's home. Robin reportedly sat at the foot of the stairs and told police the bodies were upstairs when they arrived.

He was ultimately found not guilty by reason of insanity after a trio of mental health experts decided he was too psychologically ill to understand his actions were wrong, according to a 1999 Chicago Tribune article.

Robin spent about 10 years at the Elgin Mental Health Center before a judge ruled he could be transitioned back into the community.

In 1843, McNaughton followed a British civil servant from the Prime Minister's residence and ultimately shot him in the back.

During his interrogation, McNaughton told police "the Tories in my native city have compelled me to do this. They followed me to France, into Scotland and all over to England. In fact, they follow me wherever I go… They have accused me of crimes of which I am not guilty; they do everything in their power to harass and persecute me. In fact they wish to murder me," according to an article in the U.S. National Library of Medicine.

McNaughton was ultimately acquitted on the grounds of insanity and forcibly institutionalized.

When the English public protested the verdict, the House of Lords asked a panel of judges to create guidelines for juries to follow in insanity cases, which set the precedent both abroad and in the U.S. for all subsequent insanity cases, according to The Daily Caller.

Du Pont, an heir to the chemical company's fortune, was convicted in 1997 of shooting Olympic wrestler David Schultz in front of his wife Nancy Schultz.

But, the conviction came with a catch. The jury found he was guilty of third-degree murder, meaning murder without premeditated intent, according to a Washington Post article from the day he was convicted.

As part of the jury's agreement that du Pont was mentally ill, he was ordered to receive psychiatric treatment while incarcerated, according to The Daily Caller.

He was also spared a life sentence because he was mentally ill. He technically could have been released in as little as five years, the Washington Post reported at the time.

But the Du Pont heir died in prison at the age of 72 in December 2010, The New York Times reported at the time.

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