The Dutchman, 22, is accused of killing Peruvian business student Stephany Flores, 21, in his Lima hotel room May 30. He's confessed, but claims the confession was coerced and he was tricked into giving it, and he wants it tossed out. He also remains the chief suspect in the 2005 disappearance in Aruba of Alabama teen Natallee Holloway.
Van der Sloot told a Dutch newspaper he's received dozens of marriage proposals from women sending him letters.
What are those women -- and others who've sought relationships with other criminals -- thinking?
It has little to do with the men, and more to do with the women themselves, Northeastern University criminologist Jack Levin explained on "The Early Show" Wednesday.
Men may be notorious killers but, says Levin, they have somehow become the new celebrity, showing up everywhere from magazine covers to T-shirts.
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"These women would love to date and marry a rock star or a rap idol," Levin pointed out. "But if they send a letter to a rock star, they're lucky if they get some kind of computerized signature on a photograph and that's it," explained Levin. "These new celebrities, these inmates, are very different. These women may actually get a marriage proposal." The appeal of those inmates is getting the response.
Even someone like Van der Sloot who, a psychological evaluation found, has no respect for women is still a seductive candidate, because these women believe he isn't guilty.
"These guys are so shrewd that they talk the women into believing they are innocent victims of injustice," said Levin. "Sometimes, the women who end up dating or even marrying these guys are given a mission, a purpose in life. They are going to show the world that their man is innocent."
As for Van der Sloot himself, he knows he is in hot water this time, Levin says, adding Van der Sloot is using the same tactics he used years ago in Aruba as what Levin calls "a manipulative sociopath.
"But this time, it's not going to work, because there's a tremendous amount of physical evidence against him. That's going to make all the difference," said Levin.