i love everything about nicky. she was a phenomenal, amazing person. she loved those girls. pretty much her pride and joy. it's hard for me to even -- 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 nicky had a second boyfriend. >> two boyfriends? >> two boyfriends. >> jealousy, passion, revenge? >> she was fearful. >> she contacted the police. >> what secrets might the twins reveal? >> it's terrifying. is it possible that this could happen? >> i was shaking. oh, my god. oh, in i god. i couldn'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, good schools, the sheen of newness.

it was really pure luck that brought nicky 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 nicky whitehead's life was. >> i loved everything about nicky. >> reporter: dr. harris grew up

with nicky. she was a wild child and pretty and fun, irresistible. >> nicky was -- to me, he was a phenomenal, amazing person. >> reporter: and she was effervescent said nicky's mother, linda. bigger than life. >> she's the kind of person that when she comes in the room, she just take over the space, you know, with her personality, her laughter. >> reporter: but when nicky was 12, ooh, boy, a handful. linda was a single mom with other kids at the time, so she agreed to let young nicky move in with della, nicky's grandmother. the problem was that della let the girl run wild. boys and parties. >> we grew up kind of fast. then later she became pregnant at the age of 18 or 19. so we move kind of fast. >> reporter: yeah. >> yeah. >> reporter: pregnant with identical twins whom she named jazz and as thtaz.

their dad was around briefly then gone. and their mother figure? nicky's grandmother, della. nicky's mother, linda, didn't like that. >> i wanted nicky 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. but nicky had learned how to style hair and was doing well at it. and eventually saw the possibility of independence. so she eventually wanted to kind of get out from della's control. >> definitely. she did. she wanted to -- as the girls got older, she definitely wanted to take control of her life. >> reporter: then one day in 2000, nicky was shopping at the mall and robert head just happened to be in exactly the right spot. >> i was sitting there one

afternoon at about 6:00. and there walks nicky coming into the mall. >> reporter: your eye caught? >> yes, i 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 nicky 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. and everything clicked just right. >> reporter: and she wanted her life to get even better. so while she kept her job as a hairstylist, she enrolled in atlanta's bauder college to

study fashion design. >> that's when i actually learned that nicky was a hairstylist. >> reporter: she thought nicky had a sense of purpose, whether it was about her kids, her fashion or other people's hair. >> i came to class early one day, as i normally do. she looked up at me, what's going on with your hair? and i said, what? excuse me? and she asked me this question. do you have a hairstylist and does she know you have your hair looking like that today? i said yes and no. i'm giving her one more chance. one more chance, and if it's not right, i'm taking over. >> reporter: rhonda loved nicky and nicky 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 the of them, you know, one on each of nicky's arms. >> reporter: katie beck is a

reporter at nbc affiliate wxia in atlanta. >> teachers describe them that way, that they had a sweet demeanor in their classrooms and with their classmates. they were almost timid. >> reporter: then, as they reached their teens, they changed somehow. in the ways children often do and the way nicky herself once did. and just like nicky, the twins were sent to live for a couple of years with the rather permissive family matriarch, della. until, 2010, when nicky welcomed taz and jazz back. all together again in robert's house. a fresh start. and nicky turned up at school beaming. >> she was in a very good mood. she looked great. she had a new look with her hair. and she had braids in and she was 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: you start thinking about her? >> yeah. 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 their screams as they came pounding on his car. >> one of the twins ran up and literally beat on the side of his car and told him that they had come home from school and found their mother murdered. >> when we come back, exactly what had happened? >> they were going in and out of fits and tears and crying, traumatized. disturbed. >> two distraught daughters are about to reveal a clue. >> we're told by the twins that nicky had a second boyfriend. >> two boyfriends? >> two boyfriends. on this cushion for generations.

alright kiddos! everybody off the backpack, we made it to the ottoman. i like to watch them clean, but they'll never get me on the mattress! finally there's a disinfectant mist designed for sofas, mattresses and more. introducing new lysol max cover. its innovative cap has a 2x wider spray that kills 99.9% of bacteria. max cover is another great way to lysol that. ...meta appetite control. you and temptation with... clinically proven to help reduce hunger between meals. new, from metamucil, the #1 doctor recommended brand.

squuuuack, let's feed him let's feto the sharks!sharks! yay! and take all of his gold! and take all of his gold! ya! and hide it from the crew! ya...? squuuuack, they're all morons anyway! i never said that. they all smell bad too. no! you all smell wonderful! i smell bad! if you're a parrot, you repeat things. it's what you do. if you want to save fifteen percent or more on car insurance, you switch to geico. it's what you do. squuuuack, it's what you do. put under a microscope, we can see all the bacteria that still exists. polident's unique micro clean formula works in just 3 minutes, killing 99.99% of odor causing bacteria. for a cleaner, fresher, brighter denture every day. wopen up a lot of dawn. tough on grease...yet gentle. dawn helps open... something even bigger. go to facebook.com, dawn saves wildlife. first you start with this.

these guys. a place like shhh! no. found it! and definitely lipton ice tea. lots of it. a lipton meal is what you bring to it. and the refreshing taste of lipton iced tea. are how clear windexith makes your windows? introducing...schmindex! look! windex makes glass too spotless and too dangerous... but shmindex makes it dirty shmindex. order yours today lashblast is our most coveaward winning mascara news for lashes! millions of girls, millions of looks billions of beautiful lashes blasted! the lashblast collection from easy, breezy, beautiful covergirl

wednesday afternoon, 2010, a gated community in the town of conyers, east of atlanta, twins yasmiyah and tasmiyah arrived home in school, walked in the door, followed the bloody trail and there she was, in the bathtub. their mother, 34-year-old nikki whitehead very, very dead. >> we walked in. >> reporter: the mess that greeted arriving conyers

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 laceration to the back of her head. there was blood on the door, on the door handle. >> reporter: as if somebody tried to get out. >> tried to get out, yep. then along this wall, you can see a bloody imprint of hairbraids 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 her at the base of her neck. >> reporter: a 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 discover their mother murdered. >> reporter: conyers police captain jackie dunn wanted to get jazz and taz away from the house. that's when he noticed they were hurting themselves. >> one of them was biting her arm. why are you biting your arm? i'm so upset, i do that when i get upset. >> reporter: this was the worst kind of case, detectives needed information fast. but how do you get it from children who just left their dead mother? [ crying ] >> they were going in and out of fits of tears and crying. >> i want grandma. >> asking for their mom. >> i want mama. >> she both seem to be rocking back and forth, you know, contemplative, traumatized, disturbed.

>> it will be okay. >> i want grandma. >> it will be ok. >> i remember thinking, man, i hope there is a civil 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 asked me when is the last time i talked to nikki. i said saturday. you may want to go over to her house because the helicopters were there and the news reporters. >> reporter: tell me when you heard that, what did you think? >> i don't know. it was like television. i was just like in slow motion. >> reporter: yucca called her mother linda. 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, in i god. i was just shaking. >> reporter: linda pulled into

her daughter's neighborhood and saw a police officer. >> okay. 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 up to the side. i said, what is going on? i said, the only thing i can 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. >> they were looking for cell phones, computers, indications

typically the victims have called for spoken with their assailant just before the murder or around the time of the murder. >> reporter: the attack did not look random. it was not 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 explains 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: that takes a while, right? >> yes, sir.

>> reporter: meanwhile, detectives spread out through the neighborhood, knocking on doors. had anyone seen anything unusual? a 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 on the street, too. they asked the girls who could have been there? >> does your mom have any other friends or anybody else that come over that you know of. >> she talks to a lot of men. >> she talks to some men. but the only one i've been hearing her talk 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? >> they were clearly having an argument, yelling screaming over

the phone. he was an immediate person of interest.

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, jas and tas, 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 to 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. >> it was joe? >> reporter: their mother had a second boyfriend, a man named joe carter, a local barber whose shop was right next to nikki's salon. love triangle? now the homicide detectives thought was a potential recipe for murder. they talked to robert who was on the road in his long haul truck.

how does he react to any of this? >> he was devastated. >> reporter: easy enough to check on roberts. gps records put him a full day's drive away when nikki was murdered. when they met him, as we did, they could plainly see his grief was real. >> because that was my better half, and she's 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, 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 and when he was home he expected for her 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? >> you know what joe drives? >> no. i know the black car in that driveway. and it's a black car. >> reporter: rockdale county district attorney richard reed. >> we need 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 in a relationship. >> it can be a dangerous time in a relationship. >> reporter: it wasn't hard to track joe down. 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 did he react when you came to see him? >> he immediately started weeping. >> reporter: he didn't know about the -- 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. 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. >> looked at his hands, 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 that 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, there 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. it 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. >> reporter: 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 encountered in their own police file 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. >> a physical fight? >> a physical fight. and she contacted police. the worst thing about toilet germs? they don't stay in the toilet. disinfect your bathroom with lysol bathroom trigger... ...lysol power foamer... ...and lysol toilet bowl cleaner. they kill 99.9% of germs including e. coli. to clean and disinfect in and out of the toilet...

...lysol that. your current gel antiperspirant wet ais.sticky now, we're going to show you how degree dry spray is different. degree dry spray. degree. it won't let you down. wopen up a lot of dawn. tough on grease...yet gentle. dawn helps open... something even bigger. go to facebook.com, dawn saves wildlife. what are you doing? sara, i love you, and... [phone rings] ah, it's my brother. keep going... sara, will you marry... [phone rings again] what do you want, todd???? [crowd cheering] keep it going!!!! if you sit on your phone, you butt-dial people. it's what you do. todd! if you want to save fifteen percent or more on car insurance, you switch to geico. it's what you do. i know we just met like, two months ago... yes!

[crowd cheering] [crowd cheering over phone] this pimple's gonna aw com'on.ver. clearasil ultra works fast to begin visibly clearing up skin in as little as 12 hours. and acne won't last forever. just like your mom won't walk in on you... forever. let's be clear. clearasil works fast. no other scents feel like glade. melt your mood with our hawaiian breeze fragrance. feel relaxed, feel glade. it's built-in backup wbraid helps stop leaks by channeling them back into the core giving you the best protection at home and on-the-go

tampax. power over periods. 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. >> 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. jas 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. >> big argument. and it turned into a fight. >> reporter: a physical fight? >> a physical fight. it was tas and jas 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 linda, 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, would -- 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. >> she really wanted them back. really wanted them back. >> reporter: how did you know this? how did she express it? >> 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.

and jas and tas did not like it not one bit. >> so they started 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 said, they'll be fine. they'll mellow out. 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, jas and tas, answering the increasingly pointed questions of a couple of detectives. >> can you tell me what happened when you got home today? >> reporter: seemed a little odd that the girls were still wearing outdoor gloves. the detective asked, could you take them off, please? >> i need to see your hands and your arms. >> when we did that, we did see a cut on one of their hands, we

saw bruising on the knuckles and the skin marks and bite marks. >> reporter: bite mark. >> 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. >> we didn't get along yesterday. >> reporter: it was, as they told their story, detective dunn took a good look at jazz and taz 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 reason to be suspicious? >> we watched the high school video surveillance. you see the twins showing up about 2 1/2 hours after they should have for school. >> what were the girls doing the morning of the murder? guess what i just did?

built a sandcastle? ha, no, i switched to geico and got more. more? 24/7 access online, on the phone or with the geico app. that is more. go get some mud... all that "more" has to be why they're the second-largest auto insurer. everybody likes more. mhm, i think so. geico. expect great savings and a whole lot more. your heart loves omega-3s. but there's a difference between the omega-3s in fish oil and those in megared krill oil. unlike fish oil, megared is easily absorbed by your body... ...which makes your heart, well, mega-happy. happier still, megared is proven to increase omega-3 levels in 30 days. megared. the difference is easy to absorb.

school lunch can be difficult. cafeteria chaos. one little struggle... can lead to one monumental mishap. not with ziploc easy open tabs. because life needs ziploc. sc johnson. ...meta appetite control. you and temptation with... clinically proven to help reduce hunger between meals. new, from metamucil, the #1 doctor recommended brand. if you a dry mouth can be ations common side effect. that's why there's biotene. it comes in oral rinse, spray or gel, so there's moisturizing relief for everyone. biotene. for people who suffer from a dry mouth. to show your roots.

with root touch up from nice'n easy it blends with leading shades, even salon shades. in just 10 minutes. so pick your shade. and show the world your roots... ...with root touch-up. ♪ sfx: crowd cheering ♪ sc johnson this pimple's gonna aw com'on.ver. clearasil ultra works fast to begin visibly clearing up skin in as little as 12 hours. and acne won't last forever. just like your mom won't walk in on you... forever. let's be clear. clearasil works fast. it's built-in backup wbraid helps stop leaks by channeling them back into the core giving you the best protection at home and on-the-go tampax. power over periods.

thanks for tnorfolk!around and i just wanted to say, geico is proud to have served the military for over 75 years! roger that. captain's waiting to give you a tour of the wisconsin now. could've parked a little bit closer... it's gonna be dark by the time i get there. geico®. proudly serving the military for over 75 years. 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, linda, remembered clearly how angry the twins were just a week earlier when the court sent them back to nikki. >> when jas came out, she looked over at my daughter and she said, if i got to go back home with you, i'm gooding 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 the 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: nowhere near on time, as the school surveillance camera confirmed. >> we watched the high school video surveillance, and you see the twins showing up about 2 1/2 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 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. tasmiyah is taken to a smaller interview room. it's apparent that tasmiyah 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 taz'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 taz's arm would be consistent as 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's blood, mixed with her likely assailants, 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 katie 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. though thut 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. >> the fatal struggle. did their mom start it all. >> she like charged forward. >> i kept telling her to stop. just stop.

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 reed was interested when, one day, defense attorneys suggested they wanted to make a deal.

>> 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. reed met the 19-year-old jazz and taz 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's 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're all going to die today. >> reporter: that's jazz. and then taz 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 jazz. >> 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 taz, 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, im 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 and threatening them. >> kill me now or i'll kill you all. >> 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 knows nikki knows 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 she watched her fade away, fiction through and there, 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 fingerprints 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 ass 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 get rid of her." to which the other twin responds -- "that's what i think also. she's 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 juvey 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 linda. >> these children have killed my child brutally, and you are 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 katie 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. >> yeah. >> reporter: what happened to them? >> it's hard for me to even -- i don't know. >> reporter: and nikki's mom,

linda 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 would talk about what college they wanted to go to. >> reporter: that's okay. >> so i'm sitting here and everybody gone. >> reporter: that's an awful tough road. >> you can't even imagine. because every morning i wake up, i think about my 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, who instead became their victim. that's all for now.

i'm lester holt. thanks for joining us. divided, a week that began with the shooting of two african american men by police officers. >> i wanted everybody in the world to see what the police do. >> and this way. with the killing of five police officers at a black lives matter rally in dallas. >> the suspect stated he wanted to kill white people, especially white officers. >> and sparked protests across the country. >> black lives matter! black lives matter! >> from policing the politics, the season seems increasingly divided. i'll talk to the head of homeland security and two top senators, a republican and democrat, each a former mayor. plus a week of violence and the presidential campaign. how can either of our decisive

candidates heal the nation? joining me for insight and analysis, michael eric dyson of georgetown university and msnbc contributor and long-time republican strategists marry madeleine and washington post columnist michael gerson. welcome to sunday's "meet the press". >> this is "meet the press" with chuck todd. >> good early sunday morning. too early to make comparisons but we live through a week that will stand out in vent history. headlines in the recent newspapers tell the story of a nation divided and at times feeling as if we're at war with itself. the shooting of two african american men and the subsequent deaths of police sparked protest, most peaceful but there

were tense confrontations. last night in st. paul, minnesota protesters clashed with police injuring two of them as marchers pushed past state troopers and closed a freeway. all of it exposed racial divisions in the u.s. and comes at a time of growing political polarization of it all with americans becoming more table separated by region, income, culture and race and the two candidates who themself are divisive and uniquely unseated to heal the country's wounds. the images are burned into the consciousness of a nation deeply polarized about race and policing. alton sterling killed by police officers while selling cds outside a baton rouge convenience store. philando castile shot dead in his car by a police officer in minnesota. >> he's licensed. he's carrying. >> the aftermath broadcast live to facebook by her fiancee h