up next, it was an ambush. >> we have a call of four people dead. >> oh my god. >> but the scene yields few clues and the motive's unclear. >> this case was tough. nothing was jumping out at us in the beginning. >> until a neighbor comes forward with a possible lead. >> they see a young man and a young woman just walking down the sidewalk dressed in all black. >> would it be enough? >> the families wanted answers, they deserved answers. >> what amazed me is it stayed a secret as long as it did. clear lake, texas, is a mecca for aerospace professionals from all over the world. it includes many affluent,

upscale neighborhoods. >> there's probably nobody in america that wouldn't mind living in these neighborhoods that are out there. >> but on a july afternoon, in 2003, that suburban calm was shattered when a teenager went to her girlfriend's house and found a bloodbath. >> emergency. >> got a call of four people dead, four victims have been shot. >> in the living room, police and paramedics found four young adults dead from gunshot wounds. they'd been dead for several hours. >> first walked in, to your immediate left was a female victim laying on her stomach. you had a male victim and a female victim on a sofa. behind them between the sofa and the far wall was a fourth male victim. >> it literally looks like a slaughterhouse. you have blood on the walls, bullet strikes, shell casings on the ground.

all the furniture is soaked in blood. >> the victims were 18-year-old tiffany rowell, who lived in the home. her boyfriend, marcus precella. 21-year-old adelbert sanchez. and 18-year-old rachael koloroutis. it looked as if the victims were watching tv and were caught off-guard by the attack. >> they were leaned back in the couch, feet up, like anyone would if they were watching a show or relaxing. they did not seem to be alarmed at all. >> these people had no idea they were about to be shot. >> it appeared as if rachael was killed while trying to call for help. >> she just dialed the 9 and the 1 key. the assailant came back to her and beat her to death. >> rachael was shot six times. and pistol-whipped. shell casings found at the scene indicated two guns were used.

one was a 9 millimeter. the other a .38 caliber. >> we were looking for at least two perpetrators. you don't see people going and carrying a 9 millimeter in one hand, a .38 in the other. >> and there was no forced entry. >> we allow scenes to talk to us. it confirms to us as detectives that they know their assailants. >> rachael's father heard the news on television. >> i pulled up on the scene, saw my wife standing out there, and a lot of people in the street. and crime tape around the house. i tried to run into the house. i was stopped by a police officer. >> sir, step the other way or you're going to jail right now. >> she's dead. >> i know, i know. >> please. >> let us do our job. >> i just could not even imagine in my mind who would do that to her and why.

rachael had no enemies. >> right now we're all left in the dark. all i know is that a phantom came in and took my sister away. >> the question nagging investigators was motive. who wanted these four young people dead? and why? ♪ you want to save money on car insurance? no problem. you want to save money on rv insurance? no problem. you want to save money on motorcycle insurance? no problem. you want to find a place to park all these things? fuggedaboud it. this is new york. hey little guy, wake up! aw, come off it mate! geico. saving people money on more than just car insurance. ♪ f provokes lust.

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♪ jesus loves the little children ♪ the day after four young people were killed in clear lake, texas, dozens of their former classmates gathered at the murder site. >> what you have to do is you have to deal with what happened. you also have to arrange this giant family event called a funeral. the other thing on my mind was finding out who did this. and cooperating and setting up an environment where the police were as enabled as they could be to do their job. >> the police realized that the two boys killed in the attack had been involved in drugs which may have been part of the

motive. >> marcus was leading a high-risk lifestyle of dealing drugs and ultimately bringing his cousin, adelbert, to help with that. it exposed rachael and tiffany to the effects of that. >> at the crime scene, investigators discovered there were 21 shots fired. 17 hit their intended targets. >> it appeared to be right off the bat a calculated shooting with very few mistakes and very, very few misses. >> there were no other weapons recovered at the scene, no firearms at the scene. >> three of the victims died from gunshot wounds. although rachael koloroutis had been shot six types, the cause of her death was blunt force trauma to her head. police also learned that 18-year-old tiffany rowell lived in the home alone after her father remarried and moved in

with his new wife. >> i thought tiffany's father lived there with her. i didn't find out till after the murders that tiffany lived there alone. >> this house was known as a party house, that there were regularly parties there. talked to different people that drugs were being used there. >> when investigators spoke with the neighbors they learned that no one heard gunshots. it was the middle of summer. the air conditioning was on and the windows and doors were closed. but close questioning revealed some important clues. >> when you're doing a neighborhood canvass, don't ask, did you see anything unusual this day? the right question to ask, did you see anything this day that you don't ordinarily see day to day? >> that's when the next-door neighbors gave police some information. >> they see a young man and a

young woman just walking down the sidewalk dressed in all black. >> renowned forensic artist lois gibson was brought in to create a composite sketch based on the neighbors' descriptions. >> all i had was two people who were really disinterested, who looked out a window briefly and saw a male and female. that is all i had. >> her first task was to deal with the obvious. race and age. the couple was white and looked to be older teenagers. >> the only thing unusual was that the girl had really large eyes. >> the neighbors also said she was wearing a bandana. using visual aids, hundreds of photographs of different facial features, gibson tried to nail down some specifics of the faces of the suspects. >> i'm going to show you some features and you're going to give me the features that look most like the person. i'm going to compose them. then when i have a rough sketch i'm going to show it to you and i'll change anything you want.

>> after two hours, gibson produced these drawings. >> all i ended up with was a really plain but pretty young girl with impossibly large eyes, and a really good-looking, plain, normal white guy with blond hair. >> they didn't look like the type of people who could commit this kind of violence. the question now, would anyone be able or willing to identify them?

once armed with composite drawings of the suspected killers, investigators visited the clear lake high school, hoping some of the victims' former classmates could shed some light on possible enemies. >> three out of four of the victims were clear lake high school students. so i think police probably focused on clear lake high school and what sort of connections and social groups they ran around in. >> but this was a dead end. >> the police -- i know because of my regular contact with them, they were turning over every rock. >> investigators had to consider

the possibility the murders were done by professionals. >> somebody came in there with a purpose. it was obvious whoever did this was going to make sure there was no living witnesses to report it to the police. >> both male victims in this case were known drug dealers. and one of them, adelbert sanchez, had family members tied to the mexican mafia. >> adelbert had family members that were incarcerated, in federal prison in texas, in florida, involved with the sale and transport of large amounts of marijuana from mexico, south texas. >> but detectives could find no connection between the mexican mafia and the murders. and despite investigators' best efforts, the trail of the killers eventually turned cold. >> there was a lot of frustration in this case, wondering, are we going to catch this person? or it's got to be this person right in front of us. >> the families wanted answers. they deserved answers. >> after three years, the families started to believe the case would never be solved.

>> your raw instinct is you want to find them yourself. and pulverize them. >> the only real evidence investigators had were the composite drawings. >> it was clear that the people who made this sketch that gave our sketch artist the information, these were going to be great witnesses. >> so rachael's father turned his grief into action. he helped raise $100,000 reward for anyone who could provide information leading to the arrest and conviction of the killers. some of that money was used to put the composite drawings of the suspects on billboards around the area. >> i had all the billboards put out around, just circling all the entries and exits to clear lake so you couldn't in or out without seeing those pictures. >> we had a lot of attention and we got a lot of phone calls. >> but the most important call came from an anonymous source to

the crime stoppers hotline. >> crime stoppers, how can i help you? >> the caller said he recognized the girl in the composite drawing. he'd met her in drug rehab. he said she'd bragged about participating in a quadruple murder. >> this woman admitted that she had killed four people. and was telling him in detail what it was like to kill four people. >> and she also told the informant something else, something only the killer would know. that one of the victims was killed while trying to call 911. >> only somebody truly on the inside would have known that. this is it. this is -- this is the tip. my heart was pounding and i was like, wow. >> the caller identified the woman as 20-year-old christine paolilla. amazingly, christine's driver's

license photo was virtually identical to the composite drawing. >> i yelled. i yelled. i sat in my office and went, yee-haw! couldn't believe it. >> christine paolilla attended high school with three of the four victims. ironically, christine had been bullied in school, but rachael koloroutis and tiffany rowell had befriended her. >> then when i called my wife and told her that it was christine paolilla, she said, "george, that's one of the photos in rachael's wallet." >> but why would christine kill the two girls who had befriended her? and even more troublesome, where was christine now? the prime suspect in the [announcer] who could resist the call... ...of america's number-one puppy food brand... ...with dha and essential nutrients

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the prime suspect in the quadruple murders in clear lake, texas, was christine paolilla. she'd been identified by an anonymous tipster who'd seen her composite sketch on a billboard. a background check revealed christine was a heroin addict. and after high school spent her entire inheritance on drugs. >> she estimated $1,000 a day

was being spent on heroin. >> using atm records, police found christine and her husband in a cheap hotel in san antonio. >> officers described it as the most disgusting place they've ever seen. unbelievable. you wouldn't believe fit you saw it. >> investigators found hundreds of syringes and dozens of boxes of drug paraphernalia scattered all over the room. >> it was horrible. there was a mist of blood that was on most of the items in the room. after they finished injecting they would expel the remaining bits of fluid in the syringe into the air and it would turn into a mist. it had a bit of blood in it. it was just horrible. >> they were probably a couple of weeks away from death. she was surviving on ritz crackers and cheese and a whole bunch of heroin. >> when questioned by police, christine, suffering from severe heroin withdrawal in this police video, admitted participating in

the murders. but said her ex-boyfriend, chris snider, was the real killer. as with christine, the composite drawing of snider was remarkably accurate. >> i was not in that house. >> okay. >> at all. >> were you in the driveway? >> i'll put anything on it, i was not in that house. >> were you in the driveway? >> just -- i wasn't in the -- in the driveway. i had -- the only house -- the closest i was to the house was when i -- when i drove up -- >> christine said she waited outside while snider killed her friends. >> he did it. >> he did it? did what? what did he say, christine? >> he shot them. >> that he shot them? >> a database search revealed the address for chris snider's parents, and they told police chris was living in south carolina.

when snider's parents told chris the police were on their way to question him, chris disappeared. >> he left his car, left his wallet, he left all of his belongings behind. >> police found his body in some nearby woods. toxicology tests showed he'd ingested a lethal dose of painkillers. >> he took the ultimate coward's way out. >> just a loser scumbag coward that knew what he was going to face. >> when police searched chris snider's belongings, they found a .38 caliber handgun and a 9 millimeter semiautomatic. >> ballistically, the guns were tested, and they were determined to be the weapons used in these murders. >> chris snider's dna was found on the .38 caliber. and despite the passage of three years, traces of rachael koloroutis's blood was on the 9 millimeter.

christine's husband told police she once admitted she was actively involved in the quadruple murders. >> she told me that when they left there, christine went back to make sure that one of them was dead. >> the one that was hit repeatedly over the head with a gun. >> faced with the evidence against her, christine later admitted one of the weapons was in her hand. >> it went off a bunch in your hands? >> it felt like a million times. even after the first time it felt like a million times. >> according to the evidence, prosecutors believe christine paolilla and chris snider both needed money or drugs. and went to the only place they knew to get it. tiffany rowell's house. the next-door neighbor saw enough of their faces to help

create the near-perfect composite drawings. since the victims knew christine, they opened the door and invited both of them inside. then they started shooting. 21 shots in a matter of seconds. after they took what they were looking for, christine told witnesses she noticed rachael was still alive and had her cell phone in her hand. christine beat rachael to death as she tried to dial 911. >> the last thing rachael koloroutis ever said to christine while she was crying, "why are you doing this to me?" and according to what christine told her husband, she just kept hitting. and hitting that girl until she was dead. >> christine paolilla was

charged and convicted of capital murder. since she was 17 at the time of the murders, she was spared the death penalty but was sentenced to life in prison. >> if you're a parent, when you lose a child, there's never closure. there's a big hole in you forever. and it never gets better. i could argue that it gets worse. >> this was an excellent example of how family members, police, and scientists all worked together to solve a difficult case. >> the clearest piece of evidence we had was finding chris snider's dna on one of the weapons. >> i will take physical evidence over an eyewitness any day of the week. and so forensics, the physical evidence at the scene, it tells a story just as good as an eyewitness up on the stand. >> their desire to get high again trumped the lives and

futures of four kids. unbelievable. she got everything she deserved. i was glad to be a part of it. up next, tragedy at a texas college. >> she's cold. >> she's cold to the touch? >> yes, ma'am. >> oh my god. >> it's very unusual for a 20-year-old girl to die suddenly of natural causes. >> tiny drops of blood could mean an accident. or a murder. >> we had no idea what had caused her death. >> there were just more questions than answers. >> eyewitnesses place a man at the scene. but are their descriptions accurate? >> had us really scratching our heads. >> bryan, texas, is a college town that lies in the shadow of texas a&m.