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disagreement with the pathologist before the procedure began.
    The detective had simply asked the pathologist to conduct a “rape kit,” a routine collection process in cases involving possible sexual assault. The body’s orifices are swabbed and the specimens transferred onto glass slides to be examined by microscope at the crime lab.
    “We don’t need that,” the pathologist announced.
    Bertocchini looked at Rosenquist. The veteran detective had, an hour before, made a point to tell Bertocchini to be sure and have a rape kit done.
    For many years, the only thing that could be determined fromblood,saliva, andsemen had been an assailant’s blood group. As there are only four human blood groups, such information could apply to any one of millions, or even billions, of people. Obviously, this had limited value to detectives hunting for a rapist or killer. Then, in the 1970s, scientists discovered elements in blood and body secretions that made it possible to match a sample to a much smaller number of people. Further advances since then have greatly perfectedDNA analysis, or “genetic fingerprinting.” When DNA is extracted from the cells contained in blood and secretions like saliva and semen, it can now be linked to a specific individual. However, there are minimum requirements to conduct DNA work: the dead body needs to be fresh enough to provide biological specimens, and there has to be an adequate sample available for this intricate testing.
    “We want to send samples to the crime lab,” the low-key Rosenquistmatter-of-factly explained to the pathologist, whom the detective knew to be one of the best in the state.
    “She was in the water,” the pathologist said. “Anysemen that was in there has been washed away.”
    Bertocchini was keenly aware that he was the new kid on the block in Homicide. He hated to start getting a reputation so soon. But dammit, this was his case, and given the circumstances of the crime, a rape kit was called for.
    “Humor me,” said Bertocchini, his voice now in a don’t-fuck-with-me growl that had caused many a street punk to stop in his tracks. He’d had enough already.
    The pathologist turned away momentarily, then went over to the foot of the gurney holding a short cotton-tipped swab that wasn’t as wide as a pencil. He pried open stiff legs.
    “You’re not going to get a thing ,” he muttered. “I don’t know why you guys even bother.”
    The pathologist shoved the swab out of sight. Quickly withdrawing it, he told the detectives: “See, you got nothing.” Using clean swabs, the pathologist next swabbed her rectum, then her mouth, rubbing the cotton tip of each onto separate slides that would be sent to the crime lab along with the swabs.
    Next, he combed out her light brown pubic hair—microscopic examination by the crime lab would determine whether her attacker had shed any of his own hair. The pathologist then made scrapings from beneath her fingernails, which would be studied under a microscope for blood and skin in the event she had scratched her attacker. Finally, he took a sample of hair from her scalp.
    Bertocchini would not be surprised when the crime lab reported later that chemical tests indicated the presence of seminal fluid on the vaginal swab and a microscopic examination of that slide detected sperm cells. (No seminal fluid or sperm cells were found on the oral and rectal swabs or slides.) The lab reported that there was not enough semen present to conduct any genetic fingerprinting DNA tests. Bertocchini felt certain that had they been able to obtain a larger sample, they might well have ended up with more conclusive evidence. Of course, until they actually had a suspect, these findings meant very little.
    Bertocchini and Rosenquist were at the autopsy that day because thepostmortem examination is a vital evidentiary link for detectives in the beginning stage of any homicide investigation. Their main concern was recovery of any and all evidence.