"But you don't believe you're wrong…"

"No. Because I'm not," I said.

It all began innocently enough, like setting out to cross a lovely country lane and suddenly being hit by a cement truck. I was in London in May 2001, promoting the archaeological excavation of Jamestown. My friend Linda Fairstein, head of the sex crimes unit for the New York District Attorney's Office, was in London, too, and asked if I'd like to drop by Scotland Yard for a tour.

"Not right now," I said, and even as the words left my mouth, I imagined how little my readers would respect me if they knew that sometimes I just don't feel like touring one more police department, laboratory, morgue, firing range, cemetery, penitentiary, crime scene, law-enforcement agency, or anatomical museum.

When I travel, especially abroad, my key to the city is often an invitation to visit its violent, sad sights. In Buenos Aires, I was given a proud tour of that city's crime museum, a room of decapitated heads preserved in formalin inside glass boxes. Only the most notorious criminals made it into this gruesome gallery, and they had gotten what was coming to them, I supposed, as they stared back at me with milky eyes. In Salta, in northwestern Argentina, I was shown five-hundred-year-old mummies of Inca children who had been buried alive to please the gods. A few years ago in London, I was given VIP treatment in a plague pit where one could scarcely move in the mud without stepping on human bones.

I worked in the Office of the Chief Medical Examiner in Richmond, Virginia, for six years, programming computers, compiling statistical analyses, and helping out in the morgue. I scribed for the forensic pathologists, weighed organs, wrote down trajectories and the sizes of wounds, inventoried the prescription drugs of suicide victims who would not take their antidepressants, helped undress fully rigorous people who rigidly resisted our removing their clothes, labeled test tubes, wiped up blood, and saw, touched, smelled, and even tasted death because the stench of it clings to the back of one's throat.