29-year-old Thomas "Bart" Whitaker, an intelligent, well-spoken young man from a model American family, who grew up with loving parents and a brother who adored him, is currently sitting on death row in Texas. Bart Whitaker is awaiting execution for a brutal crime that sent shockwaves through his hometown of Sugar Land, Texas: hatching a plot to kill his entire family.
In December 2003, Whitaker's mother Tricia Whitaker, brother Kevin Whitaker, and father Kent Whitaker were ambushed by a masked gunman as they walked in the front door of their Sugar Land home after a night out. Tricia and Kevin died from their gunshot wounds, but Kent survived. Bart Whitaker was shot as he faked a struggle with the fleeing gunman, and police initially thought he was a victim as well.
But in the following weeks, Bart Whitaker's story began to unravel, and Sugar Land police sgt. Marshall Slot began to see him as less of a victim and more of a suspect. Almost two years later, after a case full of twists and turns that included discoveries of prior unsuccessful murder plots, Bart's escape to Mexico, the confession of a getaway driver and the dredging up of a bag of evidence from the bottom of a lake, police were finally able to arrest Bart Whitaker and charge him with hiring two accomplices to help kill the family.
At his trial in March 2007, prosecutors alleged that although it wasn't Bart Whitaker himself who had pulled the trigger, he was responsible for his mother and brother's vicious murders because he masterminded the plan. The jury agreed, and convicted him of capital murder in connection with Tricia and Kevin Whitaker's deaths. His conviction made Bart eligible for the death penalty, but by this time, his father Kent had reached a conclusion that would surprise many and register as incomprehensible to some: he said he had prayed to God and asked for guidance, and God had told him to forgive. So Kent Whitaker forgave his son, and pleaded with the jury to spare Bart's life.
Both Bart and Kent Whitaker claim that Bart is a changed man, one who realizes he made mistakes, feels remorse and takes responsibility for his actions. But to many, the brutality of the murders combined with a lack of a clear motive suggests that Bart Whitaker isn't a repentant, but a cold-blooded murderer, a sociopath who deserves nothing less than a death sentence.
The shocking story is detailed in Kent Whitaker's book, "Murder by Family: The Incredible True Story of a Son's Treachery and a Father's Forgiveness." The following excerpt was provided by the publisher to ABC News.
Watch the story Friday on "20/20" at 10 p.m. ET
I had always heard that your life flashed before your eyes. But that's not what happened as I lay on the cold concrete that December night, watching the blood from a gunshot wound cover my white shirt. Instead, I found myself praying for my family. There had been four shots, one for each of us.