prosecutors were determined to punish this mother, even though the teenager in the case, bubba frank,t wanting to testify in trial. in fact, he didn't want this to be reported in the first place. >> reporter: but make no mistake, bubba's mother wanted linda lusk to pay. >> what she did to my child was wrong. >> reporter: she told us she never once doubted her son's story. >> you know your children. you know. and immediately, i knew. immediately. there was no doubt in my mind at all, not one time. >> reporter: but linda lusk would put her version of the story to the test. she took a polygraph, adamant the oral sex never happened, and she passed. defense attorney larry stephenson says that is where the case should have ended. >> the polygraph that she took, the disclosure that she's had, her history, everything about her indicates that she's not a sex offender. and damn it to hell anyway, there should have been some way to avoid it. >> reporter: but the case would go on. and in court, prosecutor andy miller would ask linda lusk about something she'd told the police, that she had touched