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10 Uses of the Insanity Defense

Jeffrey Dahmer
Dahmer’s July 23, 1991 mug shots. © Ralf-Finn Hestoft/CORBIS
Dahmer’s July 23, 1991 mug shots. © Ralf-Finn Hestoft/CORBIS

Just as John Hinckley, Jr.'s successful use of the insanity defense stunned the nation, Americans were also surprised when Jeffrey Dahmer's insanity plea was rejected.

Dahmer was charged with two counts of first-degree murder and 13 counts of first-degree intentional homicide between 1978 and 1991. All were young men whom he not only murdered but also mutilated (some he attempted to lobotomize while they were still alive, others he molested) and dismembered, keeping their heads and genitals in his refrigerator -- to be eaten at a later date. Sometimes, he had sex with the corpses.

Dahmer's case went to trial in 1992, and while he originally he pleaded not guilty, he changed his mind and his plea to guilty by virtue of insanity. The jury, however, was not convinced of Dahmer's insanity at the time of his crimes, found him guilty on all charges, and sentenced him to 15 consecutive life terms.

In 1994 while on prison work duty, Dahmer was killed by fellow inmate Christopher Scarver.

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