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Crime News Serial Killers

Can You Figure Out Who The Dumbest Serial Killers Were?

Our interactive ranking shows who true crime fans think is the least intelligent serial killer — and see after you vote who actually had the lowest IQ.

By Gina Tron

How much of a serial expert are you? Do you know who the dumbest ones were?

Average intelligence is considered to be between 90-110 IQ. Even though serial killers are commonly portrayed as evil geniuses in the movies, studies have shown that they are actually more on the lower side of average. Jack Rosewood, author of “The Big Book of Serial Killers: 150 Serial Killer Files of the World's Worst Murderers,” told Oxygen.com that the misconception that serial killers are all geniuses may stem from the fact that the few serial killers who are highly intelligent — like Jeffrey Dahmer, Ted Bundy and Rodney Alcala. Their intelligence makes them interesting, and are therefore more studied and talked about.

But, what about the not-so-smart ones? Below are a handful of serial killers with low to average IQs. Vote which one you think has the lowest IQ. Our list ranks what people think, but you can scroll down to the bottom of the page to find out what their IQs actually were.

So, how’d you do?

Dumbest Serial Killer Roundup:

Ottis Toole: 75

He diagnosed with having a mild form of mental retardation, according to an article by Katherine Ramsland, a professor of forensic psychology.

Aileen Wuornos: 81

According to court documents, Wuornos scored an IQ of 81 back in junior high school.

Gary Ridgway: 82

He is the American serial killer with the most confirmed kills to date. He evaded police for decades. But he reportedly had IQ of just 82.

Henry Lee Lucas: 84

He reportedly had an IQ of 84, which is higher than his co-conspirator Toole.

Richard Chase: 95

According to a forensics school study, he had an IQ of 95.

Randy Woodfield: 100

Randy Woodfield, the I-5 Killer, had an IQ of about 100, according to Ann Rule’s book “The I-5 Killer.”

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