a serial killer. >> there is no way oscar ray bolin is innocent. we've got overwhelming evidence. inked forensically with these homicide cases. >> reporter: oscar bolin was a trucker. but when police go to arrest him, he isn't traveling the open road. they find him here, in ohio's lebanon prison serving 25 to 75 years for kidnapping and rape. bolin is arrested and brought to tampa. by the time he stands trial years later, he says he can't remember where he was the nights of the three murders. >> this defendant oscar ray bolin caused the death of teri lynn matthews. >> there is no tie, there is no connection to oscar ray bolin to this offense. >> reporter: the defense goes on the attack, saying the evidence is circumstantial, witnesses lied, and that the state is setting oscar up. >> the prosecution will never admit what they did. i am innocent of the murder of teri lynn matthews. i have maintained my innocence all along. i don't feel you were fair or impartial at all. >> reporter: each murder is tried separately. yet through all the testimony, the grieving mothers of all three vict