Exclusive: Craigslist Rapist, Too? DNA Examined

A source familiar with the "Craigslist Killer" investigation says Massachusetts officials are conducting DNA tests to determine whether rape charges should be added to the murder charges already filed against Philip Markoff. It was not revealed where on the victim's body the DNA material was found. The sample is being tested specifically to determine whether the biological material belongs to Markoff, another client of the victim's, or someone else.

Although many analysts have quickly pegged the case as a murder motivated by robbery, not sex, a DNA match with Markoff would add a sexual motive, changing the perception that Markoff was acting out of a desperate need for money because of a gambling habit. Recent reports that the victims' underpants were allegedly found in Markoff's apartment already suggest a sexual motive.

DNA testing in Massachusetts often takes many months, although results can be obtained in only days in murder cases, which take priority in state forensic labs. Even if the DNA is a match to Markoff, rape charges would require proof that there was sexual penetration without consent and by use of force. This might be difficult to prove beyond a reasonable doubt, experts say, given that the victim, Julissa Brisman, can't testify, and she advertised erotic massage services on Craigslist. On the other hand, law-enforcement experts say condoms are common in the adult-services industry. Thus, if the DNA is a match to Markoff, nonconsent could be proved if the prosecution can establish that a condom was not used—and that this was inconsistent with the victim's established practice.

If a rape charge is added, the prosecution will gain an advantage because they can pursue a first-degree felony murder charge under the theory that the murder occurred in connection with the commission of a rape. First-degree murder in Massachusetts carries a sentence of mandatory life behind bars. Without a rape conviction, a life sentence would come with the possibility of parole after 15 years—though it typically isn't granted until 20 years.

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