Cornwell said she will sometimes be inspired by homicide cases she sees on the news, but she often becomes strongly affected by them, and almost can't help but try to piece the cases together.
"It's painful for me," Cornwell said. "I get these really vivid images because what I know about the physical findings in a case cause me to reconstruct how it happened and I am doing that without trying to and then I am depressed for days."
Cornwell revealed she has already started writing her 20th Scarpetta novel, in which she would only say that Twitter and other modern technologies would play a role.
"These technologies -- they are wonderful, but they can be extraordinarily dangerous," she said. "Whenever anything is new, I am going to explore it in every dimension and figure out how can this be used."
Several attempts have been made to adapt the Scarpetta series into film, but so far all have fallen through. Cornwell said an original script is currently being negotiated to be turned into a major film, a project she said Angelina Jolie "is attached" to, but a deal has not been confirmed.
"There were some moments where I thought my time came and went and any theatrical adaptation of my material has already been done by everyone else," Cornwell said. "It's never over til it's over."
Cornwell said she was told in 2005 that no one wanted to see a "big screen CSI." However, investigative TV shows such as "Dexter" and "CSI" have exploded into enormously popular series, with plotlines that seem to be straight out of a Cornwell novel. While the author said she believes there is still time to bring Scarpetta to the big screen, the forensic TV shows bothered her at first.
"I was shocked. I said, 'Why didn't someone think of this while we had a chance?'" she said. "I simply opened a door and a lot of people have gone through it. I didn't invent forensic science and medicine. I just was one of the first people to recognize how interesting it is."
People's fascination with Scarpetta and forensics, Cornwell said, stems from a fundamental part of human nature that we all want to face our fears, but "in a way that is tolerable."
"It's like looking at the most dangerous animal at the zoo -- the tiger slinking past but you have to have that cage," Cornwell said. "You are not afraid. You get close enough to hear it purr, but you are not in it with it, and therefore it's safe, and my books, particularly 'Scarpetta,' give us a barrier between us and what we fear, which is violence and death."
As a kid, Cornwell said her first love was archeology and her favorite books were by Dr. Seuss, but she started her writing career as a journalist. Cornwell said she became fascinated with forensic investigations when she covered the crime beat for the Charlotte Observer in Charlotte, N.C., and worked on a story about a missing girl who was found dead on a lake shore.
"I would go to that lake shore and I would walk it myself," she said. "I would look thinking maybe there is something here that everyone has missed. Some little fragment of something that would tell us who did this, and that was the beginning of my mind working this way."