Dateline | August 16, 2013
>> a month. remote border town has been rocked by the murder of one of its brightest young stars, a pretty, athletic high school junior . her killer, one of her olest friends whose confessed, but some say his story doesn't quite add up, and now the victim's family is about to realize that when it comes to that terrible night in the desert they literally don't know the half of it. again, keith morrison .
>> it was one of mickey costanzo's favorite places, the high school track where she won so many races. now on a bright spring day in may 2011 , two months after her murder, a somber celebration was under way here. it would have been mickey 's 17th birthday.
>> i bought a cake, balloons, took it down to the high school , invited her friends and that was the hardest day next to finding out she was murdered.
>> apparently murdered by a childhood friend , kody patten. he'd confessed at the city jail the death penalty , a distinct possibility or so everyone thought, but as they celebrated mickey 's life, was there something about her death they didn't know. several days earlier kody 's legal team had a surprise visitor. kody 's fiancee, toni fratto. she arrived wearing her pajamas and with kody 's father at her side said she was ready to tell the lawyers the story.
>> so are you willing to proceed?
>> i think so, yeah.
>> we talked and we recorded that conversation with her permission and it was dynamite.
>> you're about to hear a whole new version of mickey 's murder and would turn the case upside down.
>> am i to believe that you, in fact, were present when the girl got killed?
>> and here, from the lips of this quiet little teen came a horrifying story. kody wasn't the only killer. it began for her, she said, with a text from kody meaning i have her. meaning mickey was in an suv and wanted kody to join him. kody picked her up and the three drove around, ending up at the gravel pits. then mickey and kody got out of the car and she started yelling at him and then pushing him.
>> i looked away just for, like, a split second and then heard, like a loud thus on the car or whatever. so i had got out to see what happened.
>> what did you see that had happened?
>> micaela was on the ground, and she wasn't really moving at that point.
>> she said kody started digging what appeared to be a grave and when he finished with mickey lying semiconscious on the ground they both started kicking her, punching her, hit her with a shovel.
>> she wasn't moving, and so we had moved her to the grave, and then we were kind of standing there deciding what -- what -- what do we do? we didn't know what really, we had just done. i remember, like, holding down her legs and, um, we had slit her throat.
>> who cut her throat?
>> it was both of us.
>> it was both of us. words that changed anything. toni fratto freely admitting that she had also murdered mickey .
>> all of a sudden it changed from one crazed killer to two people who committed a homicide. it gave us something to point the case towards other than kody 's acts.
>> two killers sharing the guilt. maybe with some good lawyering his client could escape the death penalty after all. why toni said those things was almost beside the point for olson, anyway, but not for toni 's patierents, not when they found out.
>> no one that knows toni would have ever seen this coming. it just isn't possible.
>> their dater hadn't even been a suspect, not even a person of interest. now she confessed herself into a murder that could send her to death row . she's been coerced into saying this.
>> somebody made her do it.
>> what person popped into your head?
>> kody 's dad.
>> kody 's father, kip patten, the man who delivered toni to kody 's lawyers, denied a request to appear on the program, but toni insisted and it was her idea to meet with kody 's attorneys. he just drove her there because toni 's parents were out of town.
>> do you think sometimes that she thought i can't do this with my parents present. i have to wait until they're gone before i can go and confess to this terrible thing?
>> i don't know. possibly so, but we've always been very, very open.
>> or possibly a misguided attempt to save kody ? but she'd only succeeded in incriminating herself.
>> she doesn't believe that she's confessing to the law enforcement . she's talking to kody 's attorneys, asking them if it's going to help.
>> but toni didn't have an attorn attorney-client relationship with kody 's lawyers, no protection. so they turned it over to law enforcement and when the detective donald burner reviewed the transcript of toni 's confession.
>> and we determined we had probable cause to arrest her just based on her own admission. toni fratto just 18 was booked, held without bail, facing perhaps a capital murder charge, same as kody .
>> i, in my heart of hearts knew toni had something to do with it because they were a couple. it was very hard for me to know she was at school wearing his engagement ring , acting like nothing had happened and she knew nothing about it when i knew she knew. i said, i am so glad that she is now sitting and facing what he is. now -- now it makes sense.
>> but little toni fratto hardly seemed like a killer. she was a beauty queen at 13. west wendover junior miss , in fact, devoutly religious, too, and extremely close to her parents.
>> she always went to church with us. a lot of kid, you have to force them to get out of bed and go. it was never that way with toni .
>> she had goals in her life. she knew exactly where she wanted to go.
>> a truly responsible child.
>> yes. absolutely.
>> outside of her family, toni had very few friends, except ko kody , of course. from the moment they started dating in the ninth grade they were virtually inseparable.
>> she loved him. she thought she loved him.
>> he was very, very possessive. did not like her time taken up by anyone else but him.
>> now the frattos remembered a possessive, controlling kody , so big and strong and when they thought about it that way they wonder, what was the real story behind their daughter's