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Who is the most intelligent serial killer?
Let’s consider human intelligence for a moment. Perhaps the best way to assess it comes in the form of the IQ test. While not quite a perfect barometer of intelligence, the test offers a pretty reliable and standardised way of testing and summarising how clever someone is.
The average person has an IQ of around 95-105. The average serial killer, according to The Serial Killer Information Center, has an IQ of 94.5. Slightly below the lower side of average. The stats prove that repeat murderers are generally slightly less intelligent than the average member of society. How about that?
That said, there are plenty of exceptions to the rule. In truth, serial killers appear across the scale of human intelligence. But what can we learn from that? Is there a connection between a killer’s IQ and their crimes? Let’s see if we can find out, shall we?
High IQ
Nathan Leopold - 210
When rich kids Nathan Leopold and Richard Loeb kidnapped a local boy - 14 year-old Bobby Franks - in Chicago in 1924, they didn't have much of a motive. At least not a traditional one, anyway. When they bludgeoned him to death and dumped his corpse it wasn't for financial gain or revenge. It was merely to see if they could get away with it.
Leopold and Loeb were arrogant thrillseekers who later became the basis for the Patrick Hamilton play and Alfred Hitchco*ck film Rope. Both were smart, but it was Leopold who devised the fiendish plan. He was, unequivocally, a genius. However, their plan was ultimately terribly conceived and executed, and the pair were rather quickly apprehended by police.
Ted Kaczynski - 167
Technically classified more as a ‘domestic terrorist’ than a serial killer, The Unabomber is still worthy of note here. After all, he did kill people. And he does have a fierce intelligence. The former professor of mathematics-turned-murderous-anarchist had a prodigious intellect and an IQ higher than that of Albert Einstein’s.
Unabomber Ted J Kaczynski Image – Image Credit: ZUMA Press, Inc. / Alamy Stock Photo | Above: 'Unabomber' Ted J. Kaczynsk. is shown in a 3rd April1996 police photo at Lewis and Clark County Jail, Montana, USA
Charlene Gallego - 160
The married couple behind ‘The Sex Slave Murders’, Gerald and Charlene Gallego, were not - as you can imagine - very nice people. After kidnapping, raping, torturing and murdering 10 young women during their reign of terror, Charlene received a lesser sentence in exchange for testifying against her husband. It was a smart move. But then Mrs. Gallego is a smart woman, with an IQ of 160.
Andrew Cunanan – 147
Andrew Cunahan was an oddly unknown character before the TV anthology series American Crime Story made him their focus for their second series, The Assassination of Giovanni Versace. Anyone who’s seen the show will know what a sly, manipulative and devious sociopath Cunahan was. And a smart one too.
Edmund Kemper - 145
He was big, he was strong, he was savage. He was also polite, friendly and a model prisoner. Edmund Kemper was many things, not least of all an enigma. He was also an extremely bright man, with brains and brawn.
Jeffrey Dahmer - 145
Few of us would use the word 'genius’ when describing Jeffrey Dahmer, but maybe we should. The Milwaukee Cannibal is one of history’s most disturbed and infamous serial killers. But he was also, according to his IQ tests, damned clever too.
Dr. Harold Shipman - 140
You don’t become a doctor without being smart (the average doctor scores around 120 on IQ tests - much higher than the average person). Nor do you very nearly get away with killing almost 250 people. Yet while his IQ suggests that Harold Shipman was a genius, his actions suggest he was a cold and heartless psychopath.
Ted Bundy - 136
Ted Bundy was charming, handsome and clever. That was his whole schtick. Let’s not forget that he was also a vicious rapist and murderer of women too, though.
Average IQ
Tommy Lyn Sells - 100
A violent burglar and murderer, ‘The Coast to Coast Killer’ Tommy Lyn Sells hit the exact US average for IQ when tested after his arrest.
Richard Chase - 95
The Vampire of Sacramento’s estimated intelligence was normal, even if his crimes were anything but. A rapist, serial killer, necrophile and cannibal, Chase’s back catalogue of murderous deeds is truly off the scale. Before his murderous endeavours, he was an average student who completed high school with average grades and no disciplinary problems.
Low IQ
Henry Lee Lucas | Henry Lee Lucas Image – Image Credit: Everett Collection Inc / Alamy Stock Photo | Above: Henry Lee Lucas confesses to hundreds of murders, during his trial in the mid-1980's.
Henry Lee Lucas - 85
While he scored low on IQ tests, was dyslexic and had ADHD, Henry Lee Lucas was - at least in the context of the murdering duo he was a part of - ‘The Smart One’. He scored a full 11 points higher than his criminal associate Ottis Toole.
Fred West - 84
A school dropout who worked most of his life as a labourer, Fred West’s mental capacity was such that Gloucestershire Police allocated him an ‘appropriate adult’ during interviews. His low intelligence could account for how easily manipulated he was by his wife Rose who, it’s widely believed, was the ‘brains’ behind the married couples evil deeds.
Gary Ridgway - 82
The Green River Killer killed 50-70 women between 1982 and 2001 in the state of Washington. That’s a full 20 years that Gary Ridgway murdered with impunity, evading police capture. Yet he wasn’t a mastermind criminal. He was a factory worker with an IQ well below that of the average Joe.
Aileen Wuornos - 81
History’s most notorious female serial killer, Aileen Wuornos’ score suggests low intelligence, but the reality may well differ. It’s thought that Wuornos dismissed and resented the idea of being tested and deliberately didn’t complete it to the best of her ability.
Otis Toole | Ottis Elwood Toole Image – Image Credit: Associated Press / Alamy Stock Photo
Ottis Toole - 75
Henry Lee Lucas’s killing partner was of such low intellect that he was generally considered at the time to be ‘mentally handicapped’.
Famed American criminologist Roy Hazelwood separated repeat murderers into two main groups - organised and disorganised. 'Organised' serial killers generally have above average IQs, committing crimes that are planned in advance, thought through meticulously and carried out with a steady hand. However, 'disorganised' and impulsive killers do tend to score much lower on standardised tests.
Read more:
What happened to Ted Bundy's brain after he was executed?
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