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John Wayne Gacy hated Jeffrey Dahmer -

In 1978, John Wayne Gacy confessed to dozens of murders. The police investigated and 33 deaths were attributed to him. Two years before he was executed, Gacy gave an interview where he denied comparisons with other serial killers. "God, I hate that, when they put me in the same club with them," he said. 

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John Wayne Gacy hated Jeffrey Dahmer -

Dahmer was on trial at the time of Gacy's interview and he was not declared insane. Dahmer ended up receiving 16 life sentences. Gacy however, believed the justice system failed.

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John Wayne Gacy hated Jeffrey Dahmer -

He believed someone like Dahmer was definitely insane. "If Jeffrey Dahmer doesn't meet the requirements for insanity, then I'd hate like hell to run into the guy that does," he said.

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Edmund Kemper hated Herbert Mullin -

Ed Kemper was found guilty of eight counts of homicide. He started with his grandparents in 1964, and only stopped killing nearly a decade later when he was incarcerated. While in prison, he once threw water at the man in the cell next to his. 

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Edmund Kemper hated Herbert Mullin -

That man was serial killer Herbert Mullin, whose killing spree overlapped with Kemper's. When asked by the DA why he'd done that, Kemper replied that it was to "shut him up." Evidently, the two didn't get along. 

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Edmund Kemper hated Herbert Mullin -

Kemper eventually found a way to keep Mullin quiet—he'd reportedly reward him with peanuts for his silence. Mullin died in 2022 and Kemper is still serving his sentence.

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Randy Steven Kraft and William Bonin hated each other -

In 1990, Vanity Fair reported that four serial killers met every day for a game of bridge on San Quentin State Prison's death row. Randy Steven Kraft and William Bonin were two of them. The other two were Lawrence Bittaker and Doug Clark.

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Randy Steven Kraft and William Bonin hated each other -

Writer Mark MacNamara observed their game and interviewed them at the time. According to his report, Kraft always partnered with Doug Clark. He added that Kraft and Bonin "loathe each other and refuse to play together" and that "Bonin doesn't like to play with Clark."

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Israel Keyes hated BTK -

In 2005, Dennis Rader, aka BTK (pictured) was charged with 10 counts of first-degree murder. While at first BTK didn't apologize for his actions in court, a few weeks later he showed some remorse and apologized to his victims' families. This didn't sit well with serial killer Israel Keyes.

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Israel Keyes hated BTK -

Israel Keyes said in an interview that he was not interested in giving closure to his victims' families and that BTK was a wimp for doing so.  

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Israel Keyes hated BTK -

"He couldn't understand why he came out and said he was sorry for everything he'd done," said Frank Russo, assistant U.S. attorney for Alaska, in relation to Keyes.

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Ted Bundy hated the Green River Killer -

Serial killer Ted Bundy was on death row when he decided to offer his help to investigator Robert Keppel in solving the Green River Killer case. In 1995 the investigator published the book 'The Riverman: Ted Bundy and I Hunt for the Green River Killer.' 

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Ted Bundy hated the Green River Killer -

In 2003, Sheriff Dave Reichert told to The New York Times that Bundy was somewhat jealous of Gary Ridgway— the Green River Killer—and disliked him, which is why he decided to help investigators catch Ridgway.  

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Ted Bundy hated the Green River Killer -

"It was as if Mr. Bundy was jealous of the attention the Green River killer was getting," Sheriff Reichert said. He's pictured here at the sentencing of Gary Ridgway. 

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Gerard Schaefer hated Ted Bundy -

Gerard Schaefer got away with just two murder convictions, but it's believed that he killed as many as 30 people. He didn't think much of serial killer Ted Bundy. How do we know this? Sondra London, a woman who dated Schaefer and became a true crime author, shared her story.

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Gerard Schaefer hated Ted Bundy -

According to London, Schaefer talked a lot about Bundy. He used to brag that his victim count was higher than Bundy's and that he was just his copycat "doing a poor job of it." 

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Danny Rolling hated Gerard Schaefer -

Sondra London seemed to have a type: the killer type. In addition to dating Gerard Schaefer, she became engaged to serial killer Danny Rolling. As you can imagine, having the same love interest didn't make things amicable between Rolling and Schaefer.

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Danny Rolling hated Gerard Schaefer -

In 1992, Gerard Schaefer published the book 'Killer Fiction: Stories that Convicted the Ex-Cop of Murder,' which Rolling called "well-written puke." In letters to Sondra London, Schaefer also called Rolling a coward.

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Ian Brady and Raymond Morris hated each other -

Ian Brady and Myra Hindley (pictured) murdered a number of children in what became known as the Moors murders in England in the 1960s. Raymond Morris was also a child killer, infamously known for the Cannock Chase murders.

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Ian Brady and Raymond Morris hated each other -

Raymond Morris was incarcerated in 1969, and Ian Brady was already an inmate at the very same prison. The rivalry between the two became notorious. According to a report, the two killers attacked each other with scalding hot tea. 

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Kanae Kijima hated Miyuki Ueta -

Kanae Kijima (pictured), aka the Konkatsu Killer, enticed a number of men, robbed them, and killed them. Miyuki Ueta committed similar crimes. Both were given death sentences in 2012.

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Kanae Kijima hated Miyuki Ueta -

Kijima wrote in her blog (which she kept while in prison) how she envied Ueta because a writer had covered her story. According to the Rotten Mango podcast, Kijima repeatedly called Ueta an idiot. 

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Tsutomu Miyazaki hated Kaoru Kobayashi -

Japanese serial killer Tsutomu Miyazaki, aka the Otaku Murderer, murdered four young girls in the late 1980s. A murderer called Kaoru Kobayashi was a big fan. So much so, that he called himself "the second Miyazaki." 

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Tsutomu Miyazaki hated Kaoru Kobayashi -

The original serial killer was not happy about this. "I won't allow him to call himself 'the second Tsutomu Miyazaki' when he hasn't even undergone a psychiatric examination," said Miyazaki.

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Joanna Dennehy reportedly hated Rose West -

British serial killer Rose West and her husband killed at least nine women. Rose was given a life sentence in 1995. After multiple threats by other inmates, she was moved to another prison. 

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Joanna Dennehy reportedly hated Rose West -

In 2019, Joanna Christine Dennehy, who stabbed three men to death, reportedly threatened Rose West's life before being transferred to the same prison. Luckily, West was moved before Dennehy arrived. 

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Pedro Rodrigues Filho hated Francisco de Assis Pereira -

Pedro Rodrigues Filho, aka Killer Petey, was convicted of killing 71 people. The vigilante serial killer only murdered criminals. Filho didn't hide the fact that he hated serial killer Francisco de Assis Pereira, aka the Park Maniac, who murdered at least 11 women. 

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Pedro Rodrigues Filho hated Francisco de Assis Pereira -

Pedro Rodrigues Filho told a reporter that he wouldn't be happy to leave jail without having killed Assis Pereira. However, he never delivered on that promise.

Sources: (The New York Times) (Grunge) (Vanity Fair) (Santa Cruz Sentinel) (The Anchorage Daily News) (Rotten Mango)

See also: Common myths about serial killers

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