he thought he was the father of her car. -- child. >> inmate 2012, did you know lisa techel? d before lisa married seth and ended weeks before the murder. >> at some point, did your relationship with lisa techel become sexual? >> yes, did. >> we are talking texting, are we? >> no, sir. >> we're talking sexual intercourse? >> correct. >> for lisa's father that she had a lover was a cruel blow. >> by lisa? my second thought is, i don't want to tell amy because i know she won't be happy. >> does the tincture memory at all? >> really what it did for me is i have so many questions i'll never get the chance to ask her. i love lisa. she was a human being and made mistakes. >> the graphic testimony about her affair and how police overlooked it fit perfectly with the defense's theme of a botched investigation on the rushed against seth. >> he should've been investigated. >> investigators never spoke to jason while they were building their case against seth. prosecutors contacted him days before the third trial started. >> may 2012 and sometime in june 2014, no one talked to you? >> no,

lisa. seth techel (home recording): im so lucky. dennis murphy (voiceover): but stepmom amy put on her enforcer hat when it came to lisas teenage romantic life. amy caldwell: i wanted to know who the boyfriends were. i wanted to know who their-- dennis murphy: right. amy caldwell: --parents were. i-- i was the one that they had to pass the test with. dennis murphy (voiceover): the boyfriend who passed with flying colors was a kid named seth techel. he came from a longtime local family. his grandfather had been the umpteenth-term mayor of ottumwa. mom was a social worker, dad owned a local bowling alley. and the bowling alley was where seth, as a young teen, began noticing lisa. his dad was her high school coach and seth bowled almost-- but not quite-- as well as lisa. the two worked part-time together at the lanes. they were becoming boyfriend- girlfriend and that was fine with both their families. : so you liked this young girl? doug techel: oh, a lot. yeah. lorraine uehling-techel: she was a part of our family. doug techel: yeah. d