Recently one of my writing students asked me if I ever use real people in my books. The answer is yes. And no.
The bad guys in my most recent novel, THE HOLLOW, are ruthless. Soulless killing machines that look only to up the body count. Two of them are entirely fictional. The third, Andrew Cort, was partially inspired by an inmate I saw on MSNBC's Lockup. The inmate that inspired Cort was similar in physical appearance to my character: huge, heavily muscled, tattooed. What made the guy so damned scary was his eyes. Pale blue and cold, I don't imagine anyone could look him in the eye and not flinch.
On the show, when it came time for him to leave the cell, the inmate refused. It took around six guards and a blast of pepper spray to subdue the man. I give anyone who works in corrections all the respect in the world. Don't know how they do it.
I visualized Cort looking much like the inmate and gave him a backstory. Along with a nasty disposition and a penchant for cutting people up.
I'd recommend Lockup for anyone writing thrillers and crime novels. It offers a fascinating look into the minds and actions of inmates.
For additional research and inspiration, I'd also try Tru TV's Crime Library.
What provides the inspiration for your fictional characters?