, but -- >> bart whitaker had not graduated from sam houston state. >> reporter: a tiny imperfection t became a big crack. >> he had not even been attending the university. he was listed in their records as a freshman on academic probation. >> reporter: in sergeant slot's mind, bart is now a person of interest. >> at the time you were celebrating this, are you enrolled in college? >> i don't even remember. i don't think so. >> you weren't graduating from college? >> certainly not. no. >> reporter: bart lying to his parents about attending school, when, in fact, he was hanging out in a townhouse they had given him as a present. >> we took that information immediately and went to kent whitaker first with it. >> reporter: kent is blindsided by his son's lie. >> i realized -- how could he be so stupid? i was so mad at him. i got in a wheelchair and i wheeled down to his room and i just read him the riot act about how, if he had been telling the truth, he would not be a suspect. >> reporter: he may be proven a liar, but there's still no proof that bart is a scheming killer. but then a poli