Gaining their trust before savagely murdering them. Sampsons attorneys all from outside of boston blame sampsons murder spree on a head injury. They say, he fell down the stairs when he was four years old, and that turned in to an early traumatic brain injury after several more bumps on his head over the years. I dont know any of us who have not fallen down the stairs or fallen off our bikes. We didnt have helmets when we were growing up. It happened to all of us and we didnt all turn out this way. The reporter and were expected to hear from witnesses in this case. Straight ahead at 6 00 p. M. , were going to have a little bit more about what the government says sampson did while he was serving time that makes him even dangerous while in custody. We are live if boston, robert goulston, fox 25 news. Mark developing tonight, police are estimate working to come up with a motive for deadly attacks on two iowa Police Officers. Both of these men were shot and killed without warning while the