"He and his dad, as a father-son activity…bleached the connective tissue and the hair" off rodents' corpses when they found animals who'd died under their house, says Wahlstrom.
Eventually, only a pail full of bones would remain. "It was like a personalized rattle," says Wahlstrom. "The family would call them his fiddlesticks."
But, at the time, the unusual hobby wasn't about a love for gore—it was practiced out of an interest in science. Dahmer's father, Lionel Dahmer, was a research chemist. The bone bleaching was an extension of professional expertise.
After his arrest, Jeffrey Dahmer confessed to 17 murders (of which he was convicted for 16), admitting to authorities that he ate his victims' organs and had sex with their corpses.
But killers like Dahmer don't just emerge fully formed from one day to the next. They grow up and into their murderous roles.
Dahmer's childhood was not without problems. His mother, Joyce Dahmer, suffered from depression and attempted suicide. His father, preoccupied with his doctoral work, was largely absent. David Dahmer—Jeffrey's brother—came along when Jeffrey was 5 years old; throughout childhood, Jeffrey resented him as a competitor for their parents' scant attention. Between the time Jeffrey was 6 and 8 years old, his family moved frequently before finally settling in Bath, Ohio, where Jeffrey lived until he graduated from high school.
According to Louis Schlesinger, a professor of psychology at John Jay College of Criminal Justice and an expert on serial sexual murder, none of that information correlates to Dahmer's killing spree.
"Lots of people have conflicts with their brothers and sisters," says Schlesinger. "Having your mother attempt suicide and become hospitalized is not a pleasant event, but it doesn't make you become a serial killer."
That said, Schlesinger acknowledges that there are childhood and adolescent behaviors that do correlate with the development of a serial sexual murder—starting with a preoccupying sadistic fantasy, and a compulsion to act on it.
"When you do something like Dahmer did, you don't just one day do it," explains Schlesinger. "It begins in the mind."
Wahlstrom says that, as an early adolescent, Dahmer had an "off the charts" libido, and constant fantasies about doing harm—more specifically, killing men and having sex with their corpses.
"It took up about two-thirds of his day," Wahlstrom says Dahmer told him. At age 13, Dahmer tried to actualize what was in his imagination: He'd become overcome with lust for a male jogger in his hometown of Bath, Ohio, and so one day hid with a baseball bat near that jogger's route, hoping to make his first kill. But Dahmer told Wahlstrom the man didn't go jogging that day and so he moved on.
"He was a very disturbed kid and adolescent," Wahlstrom says. "He was very isolated from the people around him."
Another strong correlate to serial sexual murder is animal cruelty. "That's clear in his case," Schlesinger says, noting that as a teenager Dahmer had impaled a dog's head on a stick in the forest behind his house.
But for Wahlstrom, the most striking anecdote Dahmer shared about animal cruelty dates from grade school.
"He'd gotten this tadpole, and brought it in to his teacher…and the teacher ended up giving it away to another kid," says Wahlstrom.
Dahmer, incensed by the perceived slight, went to that student's house and found the tadpole in an aquarium, where he exacted his revenge.
"He poured some gasoline on it and set it on fire," says Wahlstrom. "He said to me, 'If you want to call that torturing animals, I tortured animals.'"
But while animal cruelty is often a component of serial sexual murder, the strongest correlate, says Schlesinger, is the murderer himself having been a victim of childhood abuse. That's a point, Wahlstrom says, that Dahmer emphatically denied.
"He said he had very loving parents," says Wahlstrom. "[And] that blaming [his] parents for these issues was completely off the mark."
Wahlstrom, who also interviewed Dahmer's friends and family members for the killer's psychiatric evaluation (which he provided to the defense), said he didn't hear or observe anything to contradict the claim of a relatively peaceful family home.
Although his mother suffered with mental-health issues, Wahlstrom says he thinks she was a loving mother. "She had the one-year baby book, with locks of his hair and lots of pictures," says Wahlstrom. "His parents seemed in the broad range of normal."
