the sample taken from angie samota's body did not match russell buchanan. put somebody behind bars? well, yeah. >> done everything you could to convict russell and send him to death row. >> yes, absolutely. of course i did. you know, i thought this guy was it. and absolutely i was going to get him. and he wasn't the guy. so everything that i thought was truth was not truth anymore. and yes, i felt very guilty. still do. >> she felt guilty. russell felt anything but. all those years he'd been unaware of how hard sheila had worked to convict him. all he'd known was the intense heat police had applied. but even now, russell just can't seem to get the words "i told you so" out of his mouth. >> it doesn't change anything. angie's life hasn't been resurrected. but my role or lack of role in this case was put to rest. i no longer had to wonder anymore about who perpetrated this horrible crime. i no longer had to live with the idea that there were people in the police department that thought i had perpetrated this crime. >> the dallas police called him on the phone