that's the case. everything else was circumstantial. >> mr. partin had a tattoo on his body that said "live free or die" and that was his motto that he went by, either let me live free or kill me. and, ultimately, i think it speaks for itself. up next, two brutal murders put a city on edge. >> we're all bothered by it. it's hard to sleep at night. >> was this the work of a serial killer? >> there were multiple similarities between the two scenes. >> police have few clues. >> these crime scenes were all debris basically. >> but plenty of motive. >> he has obviously a hatred towards women. >> the case went cold until a lover's quarrel flew out of control. in the early 1990s, seattle, washington was one of the fastest growing cities in the country.

a nurse left seattle on vacation and never left. >> she bloomed, just like a flower. you could not believe how she looked and how she talked. and she giggled and laughed. >> but two years after renee moved to seattle, tragedy struck on a cold february night. a fire broke out in her apartment. when firefighters extinguished the blaze they found renee's body. >> the victim is face down, arms to the side, legs apart. an ice pick was found between her legs. most of her clothes had been torn off. there were only remnants of a shirt that she had been wearing. >> renee had been gagged and bound. and appeared to have been strangled to death before the fire. the origin of the fire showed a possible motive. >> it appears that the fire had

been lit between renee powell's legs. >> although there were no signs of forced entry, renee's purse and credit cards were missing. and all her electronic equipment was missing, like her tv and vcr. >> she had recently been doing laundry because there was laundry stacked on a sofa. you could tell she recently put together a pitcher of iced tea because there was a pitcher full of iced tea on the counter. and you could see where the ice cubes had melted from the heat of the fire. >> i picked up the phone and my sister's voice was very unusual. she said she's gone. she's dead. i said who's kid. she said renee. i said renee who. she said renee is. i said she can't be dead. i just talked to her. >> at the autopsy, the medical examiner found evidence that renee had been sexually assaulted. >> we just couldn't come up with that person that would be wanting renee dead. never was able to find any

person, no family, no relatives, no past lovers, no, no one at work. >> then a month after renee's murder, there was another fire in the same apartment complex. suspecting arson, police used a helicopter with heat sensors to see if any one was hiding near by, watching the fire. >> it doesn't see objects per se. it sees heat signatures or heat given out by a person. there were no suspects hiding in any of the bushes. >> when the fire was extinguished, they found another female victim. 54 year old barbara walsh. >> the similarities between the two homicide scenes and the two women were extensive. >> both barbara walsh and renee powell were single, lived alone and worked in the health care field. >> both apartments were on the first floor. there was evidence that both

women had been doing their laundry at the time their attacker entered their apartment. both women had been bound using undergarments, their own undergarments. the bindings also included electrical cords that had been cut off from lamps around the apartment. >> the killer was organized and crimes well planned. >> in both units he took down the smoke detecter before setting the fire. and even took down the doorbell ringers. he went out of his way to make sure that the fire wouldn't be discovered prematurely. >> both victims had been stabbed, strangled and burglarized. both were doing laundry in the basement before they were attacked. >> we theorized that she had left the sliding glass door unlocked when she went down to the laundry room to start a load of laundry. and when she returned, the suspect had been in the apartment. >> the similarities were too blatant to be ignored. and the conclusion too horrific

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based on the evidence, seattle police suspected the same man raped and murdered two women in the same apartment complex. residents were demanding round the clock protection. >> and that is the saddest thing that has ever happened to me, that i can't even feel safe in my home. >> we're all bothered by it. it's hard to sleep at night. and, i mean, i'm a positive person, and i hate to now look at everything i see walking down the street as some suspicious arsonist. >> the victims, renee powell and barbara walsh had no known enemies. >> she had this laugh that if anybody knew her they never forgot her laugh. a very generous person. you know, she didn't have a lot, but she was willing to help anybody. >> the nature of the murders had police checking every registered sex offender within a 50 mile radius. >> we talked to people for

weeks, trying to find something that would lead us towards a killer and came up empty. >> but what stood out most to police bass the remarkable similarity of the two cases. both victims were bound and sexually assaulted, although dna evidence was recovered from only one of them. both lived on the first floor and were doing laundry before they were attacked. both had electron eck items stolen from their apartments. and there were other similarities that detectives identified as the killer's signature. >> the signature consists of five parts, which would involve binding the victim, stabbing the victim, disposing of their body, setting fires or arson and then taking souvenirs. >> since much of the evidence was destroyed in the fire, police turned to the public for help.

and within days they got more than 600 tips. one in particular logged as number 316 caught their attention. >> we had an individual that lived nearby, a short distance, about 3 miles away that was brought to us from a domestic violence advocate at the nearby court. >> 23 year old gary dolan had a history of minor offenses, but he'd never served jail time. it was his own sister who reported him to police. she was alarmed by hundreds of incredibly lure id poems he'd written and shown her. >> most of his writings were angry writings. one in particular dealt with, with forcing a kind lady to have sex with him after he'd strangled her. >> grabbing her head and snapping her neck, the poor little old lady hit the deck. now she's dead.

there's no life in her. later tonight, i'll eat her for dinner. >> some poems talked about sexual activity with older women, sexual activity with dead people. >> i'm happy with my life. sharpening the blade of may unholy knife, this is where true hatred lies, screams of agni, my victim dies. >> police certainly knew they were working with someone who was very sick. >> gary dolan was unemployed and had no alibi for either murder. he also refused to take a polygraph test. and he wouldn't provide a dna sample. so police had to find another way to get it. >> we knew he smoked. we knew we could get dna from the cigarette butt. but we couldn't take the cigarette butt from him unless he abandoned it. >> sheriffs followed gary until they saw him outside smoking a

cigarette. they questioned him at length, hoping he'd cast the butt aside when he was finished. which to their relief he finally did. that butt was sent for testing. and the results provided yet another setback. >> the dna profile from the cigarette butt did not match the dna profile from the crime scene. >> so gary dolan was eliminated as a suspect. and for the next two years, the trail of the killer turned cold.

investigators often request a psychological profile of a serial killer, in the belief this insight will help in efforts to apprehend him. in these two murders, the victims were bound, sexually assaulted, their bodies placed in a position that would shock investigators, and then both scenes were set on fire. these elements were unusual. >> these women were substitutes. they became targets and victims because he's taken his revenge feelings, his hatred of some female in his life in acting out against them.

so he's replaced the person that's been in his life with these victims. >> for two years, investigators searched for the killer with no success. then investigators got a new lead from an unusual source. a woman incarcerated in the local prison. >> i mean, this tip is just too much to not, not handle right away. >> her name was princess gray. she was in jail awaiting trial for assaulting her boyfriend, robert parker, when he had the audacity to leave her for another woman. >> she had assaulted the new girlfriend. and then later when they were in court on that, she had also assaulted robert in the courtroom. and so she was now in jail on those assaults. >> princess gray said her ex-boyfriend, robert parker was the man who murdered renee powell and barbara walsh.

>> it was the kind of tale police had heard hundreds of times before. >> princess gray did have reason to lie. she was the jilted woman. >> but gray said she and robert lived just 150 yards away from the apartment complex where renee powell and barbara walsh were murdered. >> he started bringing stuff in the house. and i was like what are you doing? where did you get this stuff. he was just like just move, be quiet. be quiet, be quiet. so he brought the stuff in. then he put pepper all over the floor. >> inside or outside? >> inside and outside. >> the pepper would throw off the scent of any police sniffer dogs in the area. she said she still had the items parker took from the crime scenes. >> and where's that now? >> i have it. >> okay. >> at your apartment? >> yeah. >> in the couple's apartment,

investigators found the items stolen from renee powell and barbara walsh's apartments, tvs, vcrs, coats and other items identified by the victims relatives. when questioned by police, 23 year old robert parker denied any involvement in the murders. >> there were no fingerprints. there were no eyewitnesses. he never admitted to being in those apartments. >> but a background check revealed past brushes with the law. >> at the time of the murders, robert was making his money by selling drugs on the street. and it, pawning property and selling property. most likely stolen property that he got in drug trade and stuff. >> but then, princess gray recanted her story. apparently she and robert parker had reconciled their differences. princess gray now claimed they found these items in the trash.

>> she claims that he was in the apartment all night, that she had gone out and found the property by some garbage cans or a dumpster. >> without princess gray, investigators had no evidence. >> it wasn't unexpected, since her and parker shared a child. but, damn it, when you have someone who is providing you good evidence that connects the killer with the crime scenes, it's a hard nut to swallow. tes skater kid: whoa narrator: that got torture tested by teenagers and cried out for help. from the surprised designers. who came to the rescue with a brilliant fix male designer: i love it narrator: which created thousands of new customers for the tennis shoes that got torture tested by teenagers. the internet of everything is changing manufacturing. is your network ready?

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he started putting stuff in the house. >> princess gray implicated her boyfriend, robert parker in the murders of barbara powell and renee walsh. but later recanted after the two reconciled. which version was correct? >> she had facts that no one but the investigators, the victim and the suspect or someone close to the suspect would know. >> but investigators didn't give up. princess gray had given them hours of information all on tape, countless details of her life with boyfriend robert parker. some of it telling. >> was your sex life pretty normal then? >> yeah, except for one time.

we were having sex, and he started to act like he had split personalities. and he started like choking me and calling me bitches and whores and stuff. >> and she said something else about parker's personal hygiene. >> she mentioned that after they made love he frequently would go into their bathroom, clean up using their towels and leave the towels lying about their vanity. we found two towels in barbara walsh's bathroom laying on top of her vanity. >> although the towels had been in the fire, investigators wondered if parker may have used them after the sexual assault of barbara walsh. to find out, investigators took a close look at those towels. >> the towel was kind of folded or wadded up. and when it was opened it up and started to examine it, we found four hairs that were, if they weren't heat damaged, they were,

you know, they were certainly visually different from barbara walsh's hairs. >> and one of those hairs had the potential to be a gold mine of evidence. >> first hair that i glommed and to was probably the largest hair and it had a root. and had a root with some tissue on it. >> dumb luck kept that towel from burning up and burn being the pubic hair with it. >> investigators now had dna evidence from both crime scenes. biological from the rape test kit and the hair from barbara walsh's apartment. scientists compared robert parker's dna to those dna samples. >> robert parker's dna profile was compared to the profile previously generated from the vaginal swabs. it was a match. >> robert parker had denied ever be being in the victims' apartments.

and now the evidence directly contradicted him. two years after the crimes, 23 year old robert parker was arrested and charged with two counts of murder. prosecutors believe parker spent weeks watching his victims. with renee powell, he waited in the woods next to her apartment. when she went to the laundry room in the base. she left her door open. he went inside, grabbed a knife from the kitchen and hid. when rent hay returned, he attacked binds her arms with lamp cords from inside the apartment, then sexually assaulting and stabbing her to death. he grabbed some items of value, a vcr, a coat, dismantled the

smoke detecter, then set the fires to destroy evidence. the case of barbara walsh was virtually identical. she, too, was doing her laundry and had left the door open while she went downstairs. like the first it crime, parker used materials he found inside the apartment. after the sexual assault and mush der, he used the towels in the bathroom to clean um before setting the fire. in the folded towels, one hair with the root in tact survived the intense heat, smoke, and flames. a tiny hair found with the help of an angry girlfriend intent on getting revenge. investigators think the motive for parker's crimes was in part his anger and resentment towards

his girlfriend, princess gray. >> he had a lot of pent-up anger to princess, who was dominant, extremely difficult person to deal with. and i suspected that contributed to the release of this sexual deviancy that we see in the murders. >> after a four month trial, robert parker was convicted of two counts of aggravated murder and sentenced to life in prison. his crimes were planned, all the way down to his attempts to destroy the evidence. but science uncovered evidence he didn't even know existed. >> it remains incredibly unsettling that there could be other parkers just walking the streets among us. and there's nothing to tip you off. >> there are a lot of cases that would go unsolved if there was no forensic science around.

>> you just never know, because it can be microscopic. or it can be something as big as a football or something like that. it's, that's the beauty of forensic science. is you just don't know what's going to be the most part of your analysis. up next -- a college co-ed vanishes without a trace. >> the television was still on. it was almost as if her activities had been interrupted. >> it's just really scary to think about that it happened here. >> her fellow students prayed for her safe return. police feared her abductor might be among them. >> everybody was a suspect, but we had no direction to go. >> eventually, the trail led to a barn fire hundreds of miles away, a senseless murder with no motive. science played a big part in olamide adeyooye's life. ever since she was a little girl, she dreamt of a career in medical research, and e