>>epor >> reporte this ishe coffeewood prison, i mitchell virgini something like 40% of hilife. i dn't i didn't know. i was naive. you know, i was sced. >> reporter: robert isot one, of course. there are pele like him in situations just like his in jailand prisons alaround the country, who confessed as teeners rimes they maybe didn't cmi inaco prent at ver thing, police dertmes in manyther count bned dispensed years ago th inteogation techniques still us in erica. had the murr happen elsewhere, for example, here in the united kingdom it's probable th roberstill wod ha been broug in for questionin he was aer all nam as a suspt by otherinhe case. but e ances thate would haveeecharged orven intewed for very long, close toero. >> the interview as it is on the recordg would not legal in the k., and that evidence would not ve been admitt to >> repor tis andy griffiths26 years a detective in the sussex police de, internio recogned foris w veigatintew chniques. when griffit a rookie, british interration rules were much le they an thu.s. bu thet ym ened to ipate theschangein the united k

i'm sorry he lthe ve hilife, buwe had a job to and we had teither arrest him r rder or clear him. weleared him. >> but before jamie, befor krtin, before carolyn, there was another leard she s also connected tohis horrifying serieof ents. her na imisty johnson. >> if di't let him re me, he wld have killed me. >> likkris misty reported her attack to the bryan police deme.but ynobe delag it too traumatized to help lice in the investigati. >> iwas obably within a week i it my job and tn. i was scared. she nowegrets that decision. her tack happened first. monthsefore jas rdered. >> ieel ke if i would have stayed and fought him through the poli department, that possibly he wouldn't have been ablego o ht anne else. and kriin is left witthe memo of an assaulthat according to the law never really happe >> i w so angrat two people had to die orderor someelieve me. >> did the system fa? >> it failed me. it faid caron. it failed jae. >> youhink about thelot? they were total strangs to u. >> but they're my alternate fure. i mean, th're wh coulde happed to any u >> jury convicted ynob matthews

she's been in my hilife for 15 years and i didn't know who she was. >> the next day they found kevin'sgrave right behind that school where morgan said it would be. and steve was picked up nearly 2,000 miles away in colorado. >> i can't imagine him doing it. i can imagine morgan doing it. i don't know what they were thinking. >> figuring out what they were thinking was now the job. county prosecutor. and it would prove to be more complicated than expected. >> did she say you needed to go dig a hole? >> morgan hoo pointed the finger at steve, but now he was back and about to tell a very different version of events. >> on the day of the murder she's texting him, asking if the poison's working yes. and f when it's not working fast enough she says can you just pick up a shovel. >> the truth? the tale of the texts has another chapter to come. >>> coming up. who was the mastermind? morgan? >> she used him as a pawn to do her actions. >> or steve? >> he is a cold-blooded killer. >> a few >>> morgan mengle and her young lover steve shapell, were both sitting in jail for the murder of morgan's h

porter's finally going to behi bs prumab the rest of hilife. hhato live evy day with ate did. everday to think about and l ofurives he destye >> reporter: yousaying he has tohis fe in a kind of rorse, but you haven't seen any gn that there's that remorse. >> that's the only bad part. but he still h to sit there. >> reporter: today jessica is doing her best to move o febar 2015, she and jason finally got married. >> we t marrd on valentine's da while it w a gre day, it was al very samy parents werre. >> reporter:ar took his brother's place and walked her t aisle. >> she aed me to give her away, anwhat should have been my broth's job. reporteinof bittewe mont. rig. >> reporte to keep her parents' memory alive, jessica s set up a scholarsh in their names. as for that offbeat museum of a me, itllre with a long daughter as caraker >> i still feel them there. ey lovt use. momlt thahoe. i grewp there. and so i can't let that go. >> that's all for this edition of "dateline." d, of co and, of cour, i'll s you eek ninbc "nht m erolt.r alofat nbcs,ood night.ion's eatest coms togto celebt