Although most of my annual caseload involves adult corpses, many times I must autopsy children. Every case that comes through my morgue is tragic in some way, but the bodies of children who end up here are, without question, the most agonizing of all. They are tragic reminders that even children can't escape untimely and premature deaths. While I was serving as medical examiner in Texas during the 1990s, the police called me one day and announced they were bringing me the body of seventeen-month-old Danny Kansler.

The day before, Charlotte Kansler, Danny's mom, began a morning ritual familiar to most working parents. Before heading off to work, she left young Danny in the hands of a trusted babysitter who cared for several neighborhood children on a regular basis. It was the last time Charlotte would ever see her little boy alive. A few hours later, the police received a panicked 911 call.

Babysitter Hillary Turner claimed to have found Danny in his playpen, unconscious and not breathing. Lifted by helicopter to a local hospital, Danny died en route.

Hillary told the police that Danny's death was a freak accident and that she had found him already unconscious when she checked on him. But when an emergency-room doctor later examined the dead little boy, he made a troubling diagnosis after finding bruising on Danny's neck. The doctor told police Danny had been strangled. They brought in Hillary on suspicion of murder. But for a formal charge to be levied, I had to declare a ruling of homicide.

When the baby's body arrived at my morgue, I could see right away what had alarmed the ER doctor. Along with bruises on the front of his neck, I found two parallel linear abrasions on the top of the head and a linear contusion on the back of his neck. Danny also had small red spots on his face and eyes. These tiny spots, medically called petechiae, can occur because of bleeding under the skin. Often during strangulation, blood continues to pump into the head through the arteries. But the force of the strangulation stops blood from freely flowing back out of the head. Like an overfilled balloon, the resulting pressure ruptures the small vessels, causing the petechiae.

I couldn't really deduce much from this, however. It didn't look like a straightforward strangulation to me. The only thing I knew was that the babysitter found the child unresponsive, and the circumstances were unclear. The investigator's field report didn't describe the nature of the "freak accident" the babysitter claimed had taken place. The case was hazy to me. I didn't want to make any snap judgments, either, since the only thing standing between the babysitter and a murder trial was my ruling. So I made it clear that I wouldn't be rushed.

I do enough autopsies on children who are murdered, unfortunately, to know that people do not usually kill babies by strangling them. This case just wasn't making sense, and there weren't enough findings to put the remaining pieces of the puzzle together. That's when I decided we needed more information to get to the truth.

I called in my field investigators and asked them to return to the crime scene with the police, reenact the baby's death, and photograph that re-creation. Everything had to be carefully documented: the sequence of events, the way the room looked the day of the death, and so forth. Normally, I wouldn't send investigators back to the scene after the body has been removed, but there are times when I can't answer all questions in the autopsy suite. I need additional photographic evidence to see if the story fits the autopsy findings.

Back at the scene, with police and field investigators observing, Hillary told her whole story. The playpen was placed back in the position of the day of the death, and a large doll was used to represent the child.

Hillary explained that Danny Kansler was an overly active toddler who often managed to climb out of his playpen. Hillary, who had other children in her care, told Danny's mother that she needed a way to keep the child from wandering around unsupervised. Together, they came up with a seemingly simple measure to solve the problem. They decided to place something over the top of the playpen so Danny could not get out. What they chose was an empty bed frame on which you'd normally place a mattress, and it had springs strung across it. Hillary added that a plastic tub filled with toys was sitting on an end table near the playpen. She left the room that morning so that Danny could take his nap.

The investigators took photographs of the crib and surrounding area. Then based on Hillary's account, they reconfigured the scene to show how everything looked when she returned. As she entered the room, the tub of toys was on top of the bed frame, and Danny's neck was wedged between the edge of the bed frame and the edge of the playpen. Horrified, Hillary removed Danny immediately and tried to revive him, then called 911.

Back at the morgue, I examined the new photographic evidence and was able to see how the babysitter's explanation matched perfectly with the marks on Danny's neck. The pattern of injury was what I would expect to see if the child was in that position. Everything then came into focus, and I was able to put together the most likely series of events that led to Danny's death.

Originally what was thought to be a strangulation homicide turned out to be an accidental death caused by entrapment and strangulation. With the truth in hand, I called the police and told them to stop their criminal investigation. Hillary Turner was innocent. Danny's mother, Charlotte, though in the grip of grief, told me she was thankful that I had cleared her friend of any wrongdoing.

The world is an exciting place for infants and small children, who love to explore but aren't aware of the potential dangers. Being a parent myself, I know how hard it is to make your home risk free. You really do have to keep an eye on your kids all the time — which is why parents are so exhausted. There are many tragic, senseless accidents involving children every year, and I believe it is crucial to address them here. The ones I see most frequently involve sleeping accidents, choking, animal bites, burns, kids left in unattended vehicles, drowning, and gun accidents.

Excerpted from How Not to Die by Jan Garavaglia, M.D.

Copyright © 2008 by Atlas Media Corp. and Jan Garavaglia, M.D.

Permission granted by Crown Publishers, New York, NY