Jarvis Jay Masters’s early life was a horror story whose outline we know too well. Born in Long Beach, California, his house was filled with crack, alcohol, physical abuse, and men who paid his mother for sex. He and his siblings were split up and sent to foster care when he was five, and he progressed quickly to juvenile detention, car theft, armed robbery, and ultimately San Quentin. While in prison, he was set up for the murder of a guard — a conviction which landed him on death row, where he’s been since 1990. At the time of his murder trial, he was held in solitary confinement, torn by rage and anxiety, felled by headaches, seizures, and panic attacks. A criminal investigator repeatedly offered…