♪ she was a phenomenal, amazing person. she loved those girls. >> they were sweet, little twins, her pride and joy. it's hard. it's really hard! pretty, poised, perfect. her twins were her world. >> they were so precious. >> the three of them were a very tight unit. they were all she had, she was all they had. >> then came that awful day. >> these two beautiful 16-year-old girls had come home from school and found their mother murdered. >> they were rocking back and forth. traumatized, disturbed. >> what had the girls seen that day? could they provide a clue to

help crack this case? >> we were told by the twins that nikki had a second boyfriend. >> reporter: two boyfriends? >> two boyfriends. >> reporter: jealousy? passion? revenge? >> she was fearful. >> she contacted the police. >> reporter: what secrets might the twins reveal? >> it's terrifying. is it possible that this could happen? >> i was shaking! oh my god, oh my god! you can't even imagine. i'm lester holt and this is "dateline." tonight, watch for the double twist. here's keith morrison with "bad blood." >> reporter: once in a while, in a complicated life, a woman can get lucky. which is why you're looking at a sweet little town called conyers, georgia. antique downtown ringed by gated communities, good schools, a sheen of new-ness. it was, really, pure luck that brought nikki whitehead to this house, in this quiet, safe neighborhood. just far enough away from atlanta that capital of

overheated ambition down the highway. here in conyers she could give her beautiful twin daughters a better life than hers. but of course luck, fortune, fate, can go either way. sometimes in ways very hard to comprehend. >> everything about this goes against nature. >> how could somebody do that? >> it was definitely the bloodiest crime scene i've ever been to. >> reporter: in the next few minutes, you will know exactly when it happened, where it happened, how it happened. but of course the real question is why it happened. and the answer to that, as you will see, it's kind of complicated. but that's how nikki whitehead's life was. >> i loved everything about nikki. >> reporter: yucca harris grew up with nikki. could see she was a wild child and pretty and fun, and irresistible. >> nikki was -- to me, she was a phenomenal, amazing person.

>> reporter: yes, and effervescent, said nikki's mother lynda. bigger than life. >> she was the kind of person that when she comes into a room, she just take over the space, you know, with her personality, her laughter. >> reporter: but when nikki was 12, oh boy, a handful. lynda was a single mom with other kids a the time, so she agreed to let young nikki move in with della, nikki's grandmother. trouble was, said yucca, della let the girl run wild -- boys, parties. >> we grew up kind of fast. >> reporter: uh-huh. >> and then, later, she became pregnant at the age of 18 or 19. >> reporter: yeah. >> so we moved kind of fast. >> reporter: yeah. pregnant with identical twins whom she named jasmiya and tasmiya. jazz and tazz. born in 1993 the twin's dad was around briefly, then gone. and their mother-figure, nikki's grandmother, della -- nikki's mother lynda didn't like

that. >> i wanted nikki to get her own place, establish her own life and my mom would discourage that. she would, you know, find ways to tell her, "no, you're better off here." >> reporter: that's how it went for years. nikki had learned to style hair -- was doing well at it and eventually saw the possibilities of independence. so she eventually wanted to kind of get out from della's -- >> definitely. >> reporter: -- control, right? >> she did. she wanted the -- as the girls got older she definitely wanted to take control of her life. >> reporter: and then, one day in 2000, nikki was shopping at the mall, and robert head just happened to be in exactly the right spot. >> i was sitting on the fountain one afternoon, about 6:00. and there walks -- nikki coming in to the mall.

>> reporter: your eye just caught -- >> and -- >> right? >> yes. she was -- i say, "i just can't let her get away." >> reporter: that he was old enough to be her father? didn't matter. robert was in love. so he persuaded her to go to dinner that very night. he took her dancing. he bought her nice things, treated her like a lady. >> she was my movie star. that's what i call her, my movie star. >> reporter: his movie star with two sweet daughters, he also soon loved as if they were his own. and that's how nikki came here to safe, secure conyers. this is robert's house, and here they made a family. unusual, in some ways, as you will hear, but -- >> it was nice. it was really nice. everything clicked just right. >> reporter: and she wanted to her life to get even better. so, while she kept her job as a hair stylist, she enrolled in atlanta's bauder college to study fashion design. >> that's when i actually learned that nikki was a hairstylist. >> reporter: ronda anderson taught a couple of nikki's classes. she thought nikki had a sense of

purpose -- whether it was about her kids, or fashion, or other people's hair. >> i came in the class early one day, as i normally do. she looked up at me, and said, "miss anderson, what's going on with your hair?" and i said, "what, excuse me?" and then she asked me this question. "do you have a hairstylist? and does she know have your hair looking like that today?" and i said, "yes and no." and she said, "miss anderson, i'm giving her one more chance. one more chance. and if it's not right, i'm taking over." >> reporter: ronda loved nikki. and nikki loved her girls. she put the twins in dance and music classes. at school, they won awards. >> their teachers describe them as almost angelic, sweet, and happy and engaged. and there's pictures of them, you know, one on each of nikki's arms. >> reporter: catie beck is a reporter at nbc affiliate, wxia in atlanta. >> and teachers described them that way, that they had a sweet

demeanor in their classrooms, and with their classmates, and that they were almost timid. >> reporter: and then, as they reached their teens, they changed, somehow, in the ways children often do, in the ways nikki herself once did. and, just like nikki, the twins were sent to live for a couple of years with the rather permissive family matriarch, della. until 2010, when nikki welcomed tazz and jazz back, all together again in robert's house, a fresh start. and nikki turned up at school, beaming. >> yeah, she was in a very good mood. she looked great. she had a new look with her hair. she had braids in her hair, and she looked happy. >> reporter: as if the braids in her hair were kind of an announcement, her girls were back. >> they were pretty much her pride and joy. >> reporter: oh, you started thinking about her? >> yeah, it's hard. it's really hard.

>> reporter: it was january 13th, 2010. a sheriff's deputy happened to be in the neighborhood. the girls had just come home from school. the deputy saw a look of horror on their faces, heard the screams, as they came pounding on his car. >> one of the twins ran up and literally beat on the side of this car. and told him that they had come home from school and found their mother murdered. >> reporter: murdered? in this safe, gated community? exactly what had happened? when we come back -- >> i want my momma! >> they were going in and out of fits of tears and crying. traumatized, disturbed. >> two distraught daughters are about to reveal a clue. >> we were told by the twins that nikki had a second boyfriend. >> reporter: two boyfriends? >> two boyfriends.

>> reporter: wednesday afternoon, january 13th, 2010. a gated community in the town of conyers, just east of atlanta. 16-year-old twins jasmiyah and tasimyah arrived home from school, walked in the front door, followed a bloody trail, and there she was in the bathtub, their mother, 34-year-old nikki whitehead -- very, very dead. >> as we walked in -- >> reporter: the mess that greeted arriving conyers police detective chris moon told a terrible story. >> this was a long, drawn-out fight. nikki was fighting for her life for several minutes. this was not a quick attack and

over with. she fought here. she was struck in the back of the head. she had a lacerations to the back of her head. there was blood on the door, on the door handle as if -- >> reporter: as if she -- somebody tried to get out or she -- yeah -- >> was trying to get out, yeah. and then, along this wall, you could see a bloody imprint of hair braids, which, nikki had her hair in braids. where she fell, slid down the wall. the most severe blows came when she was face down in this area. this is clearly where the assailant got on top of her from behind and started stabbing the base of her neck. >> reporter: huge amount of blood here? >> yes, this was the largest pool of blood in this area right here. >> reporter: she was dead, or near-dead, when her assailant dragged her to the bathroom. and that's where she was, in a tub of water. what her daughters saw, before they ran to the street, screaming. >> as we get there, you have these two beautiful, young 16-year-old girls that discovered their mother murdered.

>> reporter: conyers police captain jackie dunn wanted to get jazz and tazz away from the house. and that's when he noticed, they were hurting themselves. >> one of them was biting their arm, and we're like, "hey, why are you biting your arm?" and she said, "i'm just so upset. i do that when i'm upset." >> reporter: this was the worst kind of case. detectives need information fast. but how do you get it from children who have just left their dead mother? >> they were going in and out of fits of tears and crying, and asking for their mom. >> i want my mama. >> they both seemed to be rocking back and forth -- you know, contemplative, traumatized, disturbed. >> it'll be okay. it'll be okay. >> i want grandma. >> it'll be okay. >> i can remember thinking, "man, i hope there is a suitable family member to adopt these

girls because they really need somebody to reach out and be good parents for them." >> reporter: word spread through the late afternoon gloom. a friend called yucca harris. >> she had asked me, "when was the last time i talked to nikki?" and i said, "well, i talked to nikki saturday." she had told me that -- >> "you may want to go over to her house," because she said that helicopters were there and the news reporters, and so -- >> reporter: tell me, when you heard that, what did you think? >> i don't know. it was like tunnel vision. i was just in slow motion. >> reporter: yucca called nikki's mother, lynda, told her something bad was going on over at nikki's. >> i was so nervous. i didn't know what to do. i was, like, "oh, my god. oh, my god." i was just shaking. i could hardly drive. >> reporter: lynda pulled into her daughter's neighborhood and saw a police officer. >> he said, "ma'am, can you pull over there?" i said, "no, i need to go to my daughter's house."

he said, "ma'am, will you just pull over there, please?" and i pulled to the side. i said, "what is going on?" he said, "ma'am, the only thing i could tell you is your daughter has expired." >> reporter: there is no getting over news like that. as nikki's family tried to take it in, investigators set to work figuring out who did this. the girls said their mother was still in her room with the door locked when they left the house for school at 7:30. >> we missed the bus, so we had to walk. >> reporter: perhaps the crime scene would yield more clues than the girls could. lieutenant chris moon headed back there. >> we're looking for, you know, cell phones, computers, indications, you know -- typically, victims are going to have called or spoken with their assailants just before the murder or around the time of the murder. >> reporter: the attack did not

look random. it was not a rape, but it was so violent. >> that suggested rage, and when you look at a rage murder, it's usually somebody very, very close to the deceased. >> reporter: so naturally the first person they wanted to talk to was the man of the house, robert head, nikki's boyfriend. but robert wasn't around. >> when is the last time you saw robert? >> yesterday. he left. he came in on sunday. he stayed for a day. he left. >> reporter: here's the thing, robert was a long-haul truck driver, which explained his absence, but not where he was, especially when nikki was murdered. >> we had to find robert, and we had to check on his gps. >> reporter: and that takes a while, right? >> yes, sir. >> reporter: meanwhile, detectives spread out through the neighborhood, knocking on doors. had anyone seen anything unusual? couple of neighbors said they

saw a red car in nikki's driveway that afternoon, a car they had never seen before. and a black car, too, on the street. they asked the girls, who could have been there? >> okay. does your mom have any other friends or anybody else that come over that you know of? >> she talk to a lot of men. >> she talk to some men, but the only one i been hearing her talk to lately is joe. >> reporter: joe? who was joe? >> we were also told by the twins that nikki had a second boyfriend, joe carter. >> reporter: two boyfriends? >> two boyfriends. >> reporter: now that got the investigators' attention. time to dig a little deeper into the life of nikki whitehead. coming up -- two boyfriends, two possible suspects? jealousy or bad blood involved? >> they were clearly having an argument, yelling and screaming over the phone. he was a immediate person of interest. >> when "dateline" continues.

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>> reporter: detectives in conyers, georgia were getting a crash course in the short life of nikki whitehead, found stabbed to death in the home she shared with her live-in boyfriend, robert, and her twin teenage daughters, jazz and tazz -- who, at least, had each other for support. >> the girls put their arms around each other and, "it's going to be okay. we're going find out who did this." they were clearly relying on

each other to get through this. >> reporter: but they were able to convey some real information. >> any idea who she was talking to? >> it was joe. >>s of joe? >> yeah. >> reporter: their mother had a second boyfriend, man named joe carter, a local barber who's shop was right next to nikki's salon. love triangle? sounded, to veteran homicide detectives, like a potential recipe for murder. first they talked to robert, boyfriend number one, who was on the road in his long haul truck. how did he react to the news? >> oh, he was devastated. >> reporter: it was easy enough to check on robert. gps records put him a full day's drive away when nikki was murdered. and when they met him, as we did, they could plainly see, his grief was real. >> because that was my better half, and she was gone. you know, it's a hard thing.

>> reporter: this was how detectives discovered the unusual nature of robert and nikki's relationship. robert told them he knew about the other boyfriend. it wasn't a secret. he didn't mind. he said he wanted nikki to be happy when he was away on the road. >> he's a truck driver. when he was home, he expected for her and him to be a couple, and when he was away, he realized that she was going to have other relationships. >> reporter: but what about joe? how did he feel about that? he was upset about something, said the twins. night before the murder, they said, joe and nikki had a nasty, loud argument on the phone. >> all she told joe was that he couldn't come over there last night. >> reporter: was there some suggestion that there might have been, you know, jealousy or bad blood involved? >> well, and that's what we immediately thought. and so, obviously, he was a immediate person of interest. >> reporter: so he was. and remember, a neighbor spotted a black car near nikki's house

the day she was killed. joe's car, perhaps? >> okay, you know what joe drives? >> no. i know the black car in that driveway. and it's a black -- black car. >> reporter: rockdale county district attorney richard read. >> we needed to look at joe carter, especially since nikki and joe had been in an argument. they were breaking up. >> reporter: that's a dangerous time. >> it can be a dangerous time in a relationship. >> reporter: wasn't hard to track down joe, he was at the barber shop where he worked. >> it was around closing time. we was ready to pack up and get out of there. and they approached me and my friends, then they basically said that she passed away. i mean she's dead. i was shocked. i was just in shock. >> reporter: how'd he react when you came to see him? >> he immediately started weeping. >> reporter: he didn't know about the -- >> no. >> reporter: or claimed not to know? >> he claimed not to know.

>> reporter: but reactions don't always tell the real story. >> they was basically asking about our relationship, when the last time i seen her, and i started to realize i was a suspect. >> reporter: detective moon did what any good detective would do, he looked for the sort of marks nikki might have left on her assailant's body. >> we looked at his hands, looked at his arms. he took off his shirt. >> reporter: but joe was clean, not a suspicious scratch on him. and detectives learned that black car outside nikki's house didn't belong to him. still, they brought him in for questioning, and hooked him up to a polygraph, and asked him point blank if he killed nikki. >> and the polygrapher determined that he was not deceptive in answering questions. >> i wanted them to find the killer, and i wanted them to know it wasn't me. >> reporter: so that's it for joe? >> it appeared that joe was not involved in the death of nikki whitehead. >> reporter: so two boyfriends and two dead ends. you know, in addition to robert head and joe carter, could have been a stranger.

could have been another -- did you look into that possibility? >> we did. >> reporter: yes, and they still wanted to know who owned another car, a red one that was also seen in nikki's driveway the day of the killing. didn't take long to find out. it belonged not to a murderer at all, but a friend. nikki had missed a hair appointment with this friend, and the friend had come by, knocked on the door and not been able to make contact with nikki and left. imagine, had she opened that door, such a grisly scene, so full of rage and passion. so who killed nikki? someone close? then, as they struggled to figure it out, investigators encounters, in their own police files, something rather stunning. coming up -- >> i just woke up and my daughter's gone! >> your daughter was abducted? >> i don't know, ma'am. she's just gone. >> family secrets.

there were a few yet to be revealed. >> it turned into a fight. >> reporter: a physical fight? >> a physical fight, and she contacted police. ♪

>> reporter: the investigation into the murder of nikki whitehead was not offering up

any usual suspects. the two men in her life, robert head and joe carter, had been eliminated. and a home invasion seemed very unlikely in her gated community. >> there was no histories of any peeping toms. no histories of assaults in the neighborhood. so we just kept coming up to dead ends. >> reporter: thing is, they felt sure, this had to be a rage murder. so violent, so protracted. which made it very likely it was someone nikki knew -- even, possibly, a family member. >> so we started getting into some of the family dynamics. >> reporter: and that's when they turned up, in police files, this remarkable incident back in 2007. one brief snippet of family history, but an event that changed everything that came after it. >> conyers 911. >> yes ma'am. i just woke up and my daughter's gone at the house. >> reporter: that was the voice of nikki whitehead. >> meaning your daughter was abducted. >> i don't know, ma'am. i woke up. the door was unlocked. she's just gone. i have twin girls.

one of them is gone. >> how old is your daughter? >> oh lord, 13. >> reporter: you can hear her terror. >> oh lord, my worst nightmare. >> do you think that maybe somebody came and got her? or do you think -- >> i don't know. i don't know if somebody came and got her, ma'am. she don't do stuff like this. i don't know. >> reporter: but a few hours later nikki learned that her daughters did do stuff like that. jazz had not been kidnapped. she'd snuck out to fool around with a boy. >> up until that day, i believe in nikki's mind she had perfect girls. nikki realized they weren't necessarily the girls that she thought they were. >> reporter: nikki was determined to help her girls avoid the mistakes she made at their age, so she cracked down -- on curfew, on boys, on cell phone use. the following months would be familiar to many parents of teenagers. screaming, slammed doors, stony silences. and then one summer night in

2008, a year after jazz sneaked out of the house -- >> a big argument. and it turned into a fight. >> reporter: a physical fight. >> a physical fight. it was tazz and jazz against their mother. and at that time, i think, she felt fearful, and she contacted police. >> reporter: was it the right decision, to call the police? that ensured the family ended up in juvenile court, nikki asking the judge to help her teach her daughters a lesson. instead? seemed to lynda, the judge was blaming nikki. >> i guess the judge thought they were too cute and too smart that, nah, they couldn't be doing, you know -- >> he did not take it serious. >> reporter: what did he decide to do? >> well, he asked my daughter, he said, "do you want your kids to come back home?" and she said, "no, your honor, not unless they understand that i'm not going to tolerate that kind of behavior."

and so he was, like, "you mean to tell me you don't want your kids to come home?" >> reporter: what nikki wanted was a court-sanctioned demand that her daughters obey the rules. but that's not what she got. instead, the juvenile court judge sent the girls to live with della, their great grandmother. what were they doing while they were at della's house? >> pretty much whatever they want. they kind of ran wild. >> reporter: and got in trouble repeatedly -- in school and out. >> shoplifting, smoking marijuana, seeing the wrong type of boys. >> well, she didn't want that. she knew, you know, she was going back to when she was their age in her grandmother's custody. she didn't want that for her kids. >> reporter: seemed to nikki that della was undermining her and had somehow stolen away the daughters who mattered to her more than anything else in her life. >> yeah, she really wanted them back, really wanted them back. >> reporter: how did you know this? how did she express that? >> she said it every day.

i want my girls. i'm going to fight for my girls. >> reporter: and in january 2010, nikki finally won. the judge ordered the girls back to nikki's. and jazz and tazz did not like it one bit. >> so they start screaming and hollering, "we don't want to go back. why would you make us go back?" >> reporter: in court they were doing this? >> yeah. >> reporter: nikki told her mother not to worry. >> she say, "i'll be fine. they'll mellow out. they'll -- you know, they'll come around." >> reporter: a few days after the court's decision, on a saturday night, nikki put on a welcome home party for the girls. >> they hugged me. you know, they kissed me. >> reporter: and that was the last time yucca saw nikki. four nights later, there they were jazz and tazz, answering the increasingly pointed questions of a couple of detectives. >> can you tell me what happened when you got home today? >> it seemed a little odd that the girls were still wearing outdoor gloves. the detective asked, could you take them off, please?

>> pull your -- it's just procedure since you were in -- i need to see your hands and your arms. move your -- off. what happened here? >> and when we did that, we did see a cut on one of them's hand. we saw bruising on the knuckles, and skin marks, and bite marks. >> reporter: bite marks? >> and we asked them to explain those. >> reporter: the bite marks could have been self-inflicted. remember the girls were so upset on the way to the station they were biting themselves. and the other cuts and scratches? the twins told the cops they had been fighting with each other. >> you all fight? >> yeah. we didn't get along yesterday. >> reporter: it was as they told their story, detective dunn took a good look at jazz and tazz. and a disturbing idea settled down somewhere in his brain. >> i haven't made up my mind, but i'm suspicious. coming up -- suspicious? were there reasons to be suspicious? >> we watched the high school video surveillance and you see

the twins showing up about two and half hours after they should have for school. >> what were the girls doing the morning of the murder, when "dateline" continues. ♪ when you just can't seem to escape... another sneeze attack... you may be muddling through allergies. don't get caught off guard. try zyrtec® dissolve tabs. powerful allergy relief, now in a tablet that starts dissolving instantly. zyrtec® dissolve tabs. muddle no more™.

- you can collect rainwater to shower with but there are easier ways to go green. like taking shorter showers, which conserves water and lowers your bill. you'll sing long ballads in the rain and short ditties in the shower. ♪ the more you know ♪ >> reporter: there's a look, a way of talking, that suggests a thing the spoken words most certainly do not say. as nikki whitehead's petite

teenage daughters told their story -- how they discovered their mother's body, how horrified they were -- the detectives watched their eyes, their tearless sobs, saw their bruises and cuts and just knew. >> they're not behaving consistent with somebody that found their mother murdered. >> reporter: mind you, there's a hurdle a person has to overcome, to imagine that these two sweet teenagers might have been involved somehow in what could only be called a slaughter. though nikki's mother, lynda, remembered clearly how angry the twins were just a week earlier when the court sent them back to nikki. >> when jazz came out, she looked over at my daughter. and she said, "if i got to go back home with you, i'm going to kill you." >> reporter: you heard this? >> i heard this, and it stunned me. >> reporter: but teenagers sometimes do talk that way. doesn't mean they actually do anything about it. so the detectives set about fact-checking the twin's version of events on the day of their mother's death.

starting with their claim that they had to walk to school that morning. >> they told us that they had overslept a little bit, that they had missed the bus and had walked to school. >> reporter: it was a rush, said the girls, but they did get to school on time. >> made all your classes today? >> yes. >> reporter: so the cops did what cops do, they checked surveillance tape from businesses along the route to school. and what do you know? >> law enforcement had observed the girls walking down the roadway next to the gas station a little after 10:00 a.m. that morning. >> reporter: no where near on time, as the school surveillance camera confirmed. >> we watched the high school video surveillance, and you see the twins showing up about two and a half hours after they should have for school. >> reporter: so the twins were caught in a lie. and it was a big one, but it wasn't proof of murder. they flatly denied any

involvement in that. even when they were put in separate rooms, they presented a united twin front. >> they wouldn't sway. there was never any disloyalty to each other. they never said a negative comment about each other. >> reporter: getting one to flip on the other was not going to happen? >> no. >> reporter: after those interviews, they released the girls. the juvenile court farmed them out to family and friends. and the police sent their dna, and photos of their injuries, like those apparently self-inflicted bite marks, off to the lab. and then they waited, pretty sure science would tell them that these sweet, little girls were anything but. did they appear manipulative to you? >> absolutely. i'll give you a for instance. jasmiyah is in one room. tasimyah is taken to a smaller interview room. it's apparent that tasimyah knows there's a camera, and there's a recording system in that room. and she starts to pray. >> i really want them to catch this person. please, god. >> she knew at some point in

time, somebody would watch that video. and they would see a young, innocent, sweet girl asking god to help law enforcement find the person who did this. >> reporter: and meanwhile, at the glacial pace these things occur, the crime lab worked on the dna and pored over those photos of the bite marks. one, on tazz's arm, was the impression of a big, ugly bite. they compared the contours of that bite to a mold of nikki's mouth. the similarity was uncanny. >> nikki was most likely the source. >> reporter: had their mother bitten them, trying to fight off an attack? >> the bite marks on tazz's arm would be consistent is if she had her mother in a chokehold from behind. and that her mother, nikki, is biting her, trying to get away. >> reporter: and when detectives saw the twins biting themselves right after the murder? maybe that was an attempt to cover up evidence. then the dna results came back. they knew they'd find nikki's blood.

but, remember, one of the twins had fresh cuts on her hand. and, sure enough, in a smear of nikki' blood mixed with her likely assailant's, a match. it belonged to one of the twins, but which one? >> they were identical twins. they have identical dna, so we don't know, couldn't tell for sure which twin the blood came from. >> reporter: by this time, the twins had been out in the world without a word from the police for five months. wxia reporter catie beck. >> i think those months built their confidence, built almost an arrogance that, "we're going to get away with this." >> reporter: so you can only imagine how it was. may 21st , 2010, just after school. how did they react to being arrested? >> shocked. they thought it was over with. it had been five months since they had heard from us. >> reporter: the arrest was big news in atlanta. two sweet little girls, charged with the murder of their mother. who would have thought?

>> i mean, people were riveted by this story. >> reporter: oh yes they were. and when the twins finally told their version of events that cold morning in january, the city was riveted all over again. coming up -- >> she threatened us. we are all going to die today. >> the fatal struggle. did their mom start it all? >> i kept telling her to stop. just stop. ♪

>> reporter: it's a complicated thing. lots to do if you're a prosecutor preparing a murder case against pretty, twin teenagers. and so d.a. richard read was interested when, one day, defense attorneys suggested they wanted to make a deal. >> and my response is, "it's great to hear it from you, but i want to hear it from them. and so i'd like to talk to your clients. i'd like to ask them questions." >> reporter: and that's how d.a. read met jazz and tazz, now 19-years-old, and heard them confess, they did kill their mother. but was it a confession, really? in fact, said the twins, it wasn't their fault. she started it. >> she starts cursing and stuff.

i think she was mad about us being late. >> reporter: that morning, they said, nikki was furious that they were late for school, and picked up a pot in the kitchen, they said, and swung it at them. >> she still calling us whores and sluts and everything like that, and stupid and everything like that. and she threatened us. i don't know. "we all going die today." >> reporter: that's jazz. and then tazz picked up the story. >> all right, so you took the pot away from your mom. what happened then? >> she kind of just like charged forward, not at me though, at jaz. >> reporter: now nikki had a knife, said the girls. they tumbled, room to room, trying to get it away from her before she cut one of them. and in fact, said tazz, that's how her finger got cut. >> i kept telling her to stop. "just stop, just stop, just stop." >> reporter: but she didn't, they said. >> so i'm trying to punch her, i guess. and i think taz stabbed her.

she stabbed her, and -- >> at this point in time, how many times did taz stab her? >> it was once. >> reporter: at some point, exhausted, the twins said they all called a truce. it didn't last long. >> and they both describe mom lunges for the knife. and when she does, it's on again. >> reporter: finally, said the girls, they overpowered their mother, who stopped struggling and moaned that she was cold. so they put her in a warm tub, tried to soothe her, even though, they said, she was still spitting mad, threatening them. >> kill me now or i'll kill ya'll." >> reporter: eventually, they said, she stopped talking, drifted off in the warm water and died. so, what did the d.a. think after listening to the girls' tale of self-defense against a mother gone berserk? did you believe them? did you believe everything they said? >> no, still don't.

>> reporter: the idea that nikki launched an attack on her own daughters? difficult to believe, said the d.a. sheer nonsense, is what nikki's mother called it. >> my daughter never have hit her kids. they never had a spanking, more or less. anybody that know nikki know that wasn't her behavior. >> reporter: it was very clear, said the detectives who worked the case, that in fact nikki was the victim of an unprovoked attack. she had at least 45 stab wounds. her spinal cord was almost severed. >> nikki fought for her life. we think she fought defensively. you can see where she's on her back some of the time, fighting off people that are attacking her from above with knives. >> reporter: as for the girls claim that they put their dying mother in the tub to keep her warm as they watched her fade away? fiction through and through, said the police. >> we think she was dead before she was placed in the tub. or she would have bled into the water, and the water would have

been bloody. they were putting her in the water, trying to wash off the crime scene, wash off the evidence. >> reporter: in truth, said the detectives, these girls were remorseless, defiant, brilliant little actresses. remember how they sounded just after their mother's death. >> i want my mommy. >> i want them to catch this person, please god. >> reporter: listen to the little darlings when they didn't know they were playing for the cameras. this was recorded in the back of a squad car just after their arrest. sweet little girls? hardly. >> they got [ bleep ] evidence. they can't do anything with [ bleep ] evidence like this. man, get real. did they find a murder with my finger prints on it or something? i get if they said they found a murder weapon. please do that! please find a murder weapon. thank you! >> they are aggressive. they are angry. they are combative. >> these [ bleep ] rednecks,

down dirty [ bleep ] cops did this [ bleep ]. >> reporter: oh, and one more thing, tucked away in one of the girl's bedrooms, police found this journal. inside, in childish handwriting, a death sentence. they were notes to each other, said the d.a., written just before the killing. "she don't care. she selfish. we got to get rid of her." to which the other twin responds, "that's what i think also. she got to go asap." >> it may be the most telling piece of evidence that the whole death of mom may have been premeditated. >> reporter: still, the d.a. worried, maybe a good defense attorney could spin the family's turbulent history -- the juvie court drama, nikki's two boyfriends -- and somehow sell a jury on self-defense. >> it would've been an ugly trial. i think to some extent it would have been a misrepresentation of nikki's life. >> reporter: so, he didn't like it much, but he let them plead guilty to the lesser charge, voluntary manslaughter.

30 years for each. not enough, said nikki's mother lynda. >> these children have killed my child brutally and you going to give them 30 years? they shouldn't even be able to walk the street. i know these are my grandkids, but come on now. i mean, if they can do this to their mom, god help us all. >> reporter: and the questions that go over and over in your head are like what? >> how everything about this goes against nature, how the person that provides for you and raises you and loves you and gives birth to you -- how you could watch that person die in a bathtub and lie about it. >> reporter: it was wxia reporter catie beck's reports that brought the story to an atlanta both horrified and fascinated. she, who first secured access to all those police video tapes, exposing these pretty little liars for all the world to see. >> it suddenly becomes clear that these girls have multiple

personalities, that they can be whoever they need to be for their own purposes, that they can morph between a fragile, disturbed, innocent teenager into sort of this demonized criminal. >> reporter: those girls you knew, those sweet little girls, what happened to them? >> it's hard for me to even -- i don't know. >> reporter: and nikki's mom, lynda whitehead, carries the helpless grief with her every day. every sleepless night without her daughter, without the granddaughters she thought she knew. >> i was so proud of them. and i knew -- and they -- and they would talk about what college they wanted to go to. i'm sorry. >> reporter: that's okay. >> so i'm sitting here and everybody gone, you know. >> reporter: that's an awful

tough road. >> you can't even imagine. because every morning i wake up, i think about our daughter and my grandkids. >> it's just a tragedy. >> reporter: one about a mother, who dared to dream that her sweet gemini twins would surpass her, and who, instead, became their victim. that's all for now. i'm lester holt. thanks for joining us. next problems for the fight of the century before the bell even rang. reaction from the fans and different kind of protest in the south bay. why these soccer players are wearing gas masks.

right now, the fight of the century is over. but not before it was delayed so that people at home could join in. >> big night for sports fans there. >> bars across the bay area were packed with people tonight. thousands at home ready to watch. instead, they got an error message. we're j