are these people making up this time? i m telling you people are confused. the time element is off. reporter: the investigators account had david camm square in the crosshairs: he came home from basketball and killed his family. it s not right. it s not right. it s not right. it s not right, guys. you re not right. you re wrong. you re wrong, wrong, wrong. the ah you re wrong darrell. you re wrong. well this is not right. you re gettin off the track. something s not right here. now fix it. they told david about physical evidence they d collected: specks of blood, barely visible to the naked eye, on the bottom of the t-shirt he wore that night. a crime scene expert s science had already told them: the husband and father did it. there s blood on your shirt and then i had the dna analyzed. this is the presumptive test, that it is high velocity blood spatter. it s scientific documentation.