Why The Insanity Defense Didn't Work For Jeffrey Dahmer

The name Jeffrey Dahmer has become synonymous with the darkest depravity that human beings are capable of. Dahmer was born on May 21, 1960, in Milwaukee, Wisconsin before being raised for much of his adolescence in Ohio. As noted by Biography, Dahmer was a withdrawn child following an emotionally damaging hernia operation in his early years. At the same time, there was also tension between his parents which some analysts believe may have impacted his emotional development. 

He committed his first murder at the age of 18 and went on to slaughter 16 more between 1978 and 1991. But while his 17 killings already put him among the worst serial killers in American history, it is the grim details of his treatment of his victims' remains that have remained especially notorious, with stomach-churning practices including necrophilia, the retention of body parts as trophies, and cannibalism among those that Dahmer later confessed to having done.

These do not sound like the actions of a sane person. But despite the horrors that he was accused of and his legal team claiming that he was of diminished responsibility due to his mental condition throughout the years of slaying, in court Dahmer was declared legally sane and fit to be sentenced for the 15 murders for which he was being tried. Here is why even crimes as monstrous as Dahmer's didn't lead to him being found insane, and what the consequences of that were.

Jeffrey Dahmer was arrested on July 22, 1991, after one of his would-be victims, Tracy Edwards, managed to escape from Dahmer's Milwaukee apartment and alert a pair of passing police patrolmen. After Edwards led the officers to the apartment from which he had escaped, they discovered Polaroid pictures of dismembered bodies. Initially, Dahmer tried to resist arrest but he was quickly overpowered. As police searched the apartment, they uncovered human remains including four severed heads in his kitchen and the preserved genitals of several of his victims.

Despite his trying to evade capture after police uncovered his crimes, Dahmer later offered full cooperation with the police in interviews, choosing to speak without a lawyer present and to lay out all of his recollections of his brutal slayings. He was also entirely open concerning his dismemberment and sexual use of their remains. "[I] created this horror and it only makes sense I do everything to put an end to it," he said at the time as he was assisting police in identifying his victims, per Brian Masters' "The Shrine of Jeffrey Dahmer." Dahmer also assisted by admitting his guilt in the courtroom, meaning that rather than the jury being tasked with ascertaining his guilt or not, their role was to determine whether he was sane and therefore responsible for his actions when he committed them.

According to Psychology Today's Travis Langley Ph.D., Jeffrey Dahmer's trial featured testimony from expert psychiatrists who had interviewed the serial killer to provide evidence to the jury. It was the jury's difficult task to ascertain whether Dahmer was indeed certifiably sane despite the severity of his actions. The psychiatrists diagnosed Dahmer with four personality disorders that underpinned his actions.

As The Washington Post reported, the personality disorders themselves didn't amount to his being insane in the legal sense: for that to happen, 10 of the jurors would have to agree that either Dahmer was unable to tell whether his actions were morally wrong or was unable to prevent himself from doing them as a result of a "mental disease." However, his disorders weren't considered mental diseases that would affect him in such a way, with details of his case including his use of subterfuge to dupe police officers showing that he had the power of self-control when required. Dahmer was also a selective killer whose crimes were committed with a high degree of premeditation.

Indeed, the report notes that despite attempting to plead insanity, his defense team's efforts were hampered by Dahmer's own admission that he knew his actions were wrong, meaning that their only chance to convince the jury that he was insane was to show he could not prevent himself from killing. "The tragedy here is I think he could have stopped at any time," said Milwaukee County District Attorney A. Michael McCann, per The  Washington Post.

The same Psychology Today piece explains why the jury in the Jeffrey Dahmer case came to their decision. While many Americans surely wanted to see Dahmer face justice for his crimes, those crimes didn't immediately inspire notions of sanity. Many would have found practices such as necrophilia, which experts at Dahmer's trial diagnosed him as having, as well as the revelation that Dahmer tried to zombify and enslave some of his victims by pouring acid into their cranial wounds as evidence that he was the very definition of insanity. But the laws around guilt and insanity verdicts are difficult to secure in court.

Those laws were largely influenced by John Hinkley Jr.'s assassination attempt against President Ronald Reagan — which Reagan survived despite being wounded. That court case, per Psychology Today, resulted in proving insanity in court much more difficult, so by the time Dahmer was being sentenced, he didn't meet the criteria. Ironically, Hinkley's crime, which was found to have been driven by delusions, was considered the work of an insane man, but Dahmer's more disturbing and horrifying crimes weren't.

Had Jeffrey Dahmer been found criminally insane it is highly probable that he wouldn't have been sent to prison, but rather would have been housed at a maximum security psychiatric hospital where he would have received treatment with the possibility of being released once he was deemed to have been cured. Instead, he was housed at Portage, Wisconsin's Columbia Correctional Institution. There, he was kept with other murderers, many of whom remained dangerous behind bars.

On November 28, 1994, two years after he had been sentenced to life imprisonment for 15 murders of young men and boys, Dahmer, who was then 34, was bludgeoned to death by inmate Christopher Scarver when they were left unsupervised in the prison gym. Though some of the relatives of Dahmer's victims reportedly celebrated news of Dahmer's death, others felt that he had evaded justice, with one mother stating: "The hurt is worse now, because he's not suffering like we are (via The Independent)." Whether Dahmer would have remained alive was he housed in a mental institution rather than prison is something we will never know.