son's a monster. >> how could a son do that? but why, bart? this is the question everybody wants to know. why? >> how could a father do the nearly impossible, forgive him? >> i don't understand it. i look it at it as a miracle. the desire for revenge had gone. >> he wants to save his son no matter what. >> he had to go to that length to feel alive. >> we can all live twice. >> i'm david muir. >> and i'm elizabeth var fwgas this is "20/20." >> death row. it is ominous. it is cold. it is a place you look at it from the outside and you know what happens inside. >> reporter: in a race against time, 38-year-old thomas "bart" whitaker's final days are ticking down on death row. now, he awaits a destiny that seems all but assured. execution, by lethal injection. his father, kent, spends these final days in a desperate hunt for mercy. on this savoring what may be his last visit with his son in prison. >> as we were leaving, we put our hands up to the glass and he puts his hand up on the other side and we smile and say we love you. and then we left. >> reporter: in texas, a state that executes more prisoners than any other in america, kent's is a fierce battle against the odds. his love, tested by a terrible twist of fate. the son he is defending plotted the murders of his wife, and his other son. >> police say a masked gunman shot the whitaker family as they returned home from dinner. mother, patricia and son, kevin, were killed. father kent and son bart were shot, but survived. >> i am the single greatest victim in this crime and nobody has to convince me of how awful the crime was. death penalty was the right choice in this case. >> reporter: the whitaker story began here, in sugarland, texas. where the sweet smell of success brought them everything they desired. it was the sugar industry that transformed this suburban backwater into one of the wealthiest towns in texas. >> sugar land is affluent suburb of houston an "all-american" town, a small town. this is a city in which kids play in the street in their front yards, it's a place where you want to raise your children. >> get back in line you little nerd! >> reporter: the whitaker family videos paint a warm picture of a loving, prosperous home. >> wave to daddy. >> reporter: tricia is a former teacher turned full-time mom. >> who's ready for christmas? >> reporter: every moment seems picture perfect. brothers inseparable since birth. >> he looked up to me and wanted to be me. and, i thought that was so ironic because i wanted to be him. >> they played with each other from the time kevin was old enough to do it, up until the end. they still did stuff together. >> look what you got. >> reporter: but who could imagine that inside that adorable little boy, was a ticking time bomb of rage. >> what was your relationship like with your parents? >> it was a good relationship. >> reporter: we first met bart whitaker in 2009, when bart spoke to former abc correspondent, mary fulginiti about his strange and violent journey. >> your family tried to love you. >> it was idyllic, yeah. >> hey bart, drive down to the stop sign for me. >> reporter: bart's bond with his father, kent, was especially close. from the moment bart learned to ride a two-wheeler, he and his father shared a passion for biking. >> we tried to figure it out one time and ended up with about 15,000 miles that we have ridden together. >> reporter: so how did the son of this loving family end up here on death row? >> i was always an independent child, and i think somewhere along in there -- can we stop for a second? >> what's bothering you right now? >> i'm just -- it's all a lot, thinking back on those days. we had a pretty close family. in terms of what was going on inside of me, that was a little different. never really fit in very well with anybody, to be honest with you. >> i think everybody knows horrible things can happen, but you just don't expect it. >> reporter: december 10, 2003, a time for celebration at the whitaker residence where bart receives a extravagant college graduation gift, a rolex watch. >> we thought we were celebrating the upcoming graduation of our son. he was supposed to be going to graduate school, going into law enforcement. >> we got ready for dinner, you know, and went to dinner. >> lots of laughter, yeah we were happy and we were teasing each other and -- but then we did that whenever we were together. >> reporter: as they celebrate his graduation, only bart knows that an intruder has quietly entered their home. his deadly plot is about to begin. >> entered the house with the key, and the alarm code. >> reporter: as kent snaps photos of his happy family, bart poses with his favorite dessert, bread pudding, decorated to mark the occasion. tricia smiling with her sons. >> yeah. i took that after we finished eating. i betcha no more than five or ten minutes before we left the restaurant, which is five minutes from our house. >> reporter: bart smiles. and yet, he knows that if everything goes as planned, in less than 30 minutes his brother, his mother and father will all be dead. >> i don't -- really know a better term for how i was feeling, other than i was on auto-pilot. i wasn't even aware of myself. we left the restaurant and drove back to the house. >> and when we came back, kevin led the way to the front door and trish was behind him. and when he stepped in, that's when the shootings happened. >> i went out to my car to get my cell phone. and i was walking back from the car when the first shots happened. >> i had been at church with my family eating dinner and had just gotten home and my pager went off, telling me to call the police department. >> reporter: sergeant marshall slot is a homicide detective. on any ordinary day, not much business for him in this town. >> sugar land for years has been known as one of the safest cities in america. for the police, this is not something the likes of which they've ever seen before. >> the dispatcher told me that four people had been shot, i initially thought she was joking with me. and i said, "you're kidding, right?" and she said, "no. i need you to respond to sugar lakes. a family of four has been shot"" >> reporter: but why would a kid who had it all try to kill both of his parents? 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well no, i'm also thinking about my heart. now it's your turn to ask the serious questions. ask your doctor about jardiance. and get to the heart of what matters. >> reporter: texas death row. on the surface, bart whitaker seems intelligent, well mannered, the son of an affluent family. so it seems inexplicable why this quiet young man awaits execution for an unthinkable crime. >> you were raised by a loving family. >> uh-huh. >> your mother loved you. your father loved you. your brother loved you, yes? >> yes, ma'am. >> but you still decided to kill them. >> i did. >> reporter: a heinous crime committed on a whim says prosecutor fred felcman. >> with bart whitaker, there's no reason why. he just wanted to, and that's what's scary about it. he didn't need their money. he didn't need their love. they had never done anything to him. he just wanted to do it. >> reporter: on the night of his graduation dinner, bart charmed his family, playing the role of the gracious man of the hour, or was he? >> you're smiling in this photo. this is like a half-hour before your family is going to get gunned down. what were you feeling in that photo? >> i was about as close to numb as a human being can get, i think. >> reporter: it was just after 8:00 when the whitaker family leaves the restaurant, and bart's secret murder plot is unfolding as he expects, just as he and his unwitting family arrive home. the whitaker family suspects nothing, but as they enter the house, bart hangs back. >> i'm on the front porch and, uh, i hear a shot, and then trish is saying, oh no, and then another loud noise, but i know you don't -- can't quite imagine this, but i didn't recognize them as gunshots. i didn't really understand what was happening. >> at the time, what were you feeling? >> nothing. nothing at first, and then the gunshots went off and shock. >> i walked up to the door. all the lights in the house were out, but the street light showed a single figure in a ski mask maybe six, eight feet away. my reaction was i wondered which one of kevin's goofball friends is playing a trick on us with a paintball gun, and i just stood there, but a moment later, i was shot too. and before i could call out to see how -- if bart was safe, there was a fourth shot from inside the house, and my reaction was, my god, he shot all of us. why? >> reporter: as shots ring out a neighbor calls 911. >> someone's just shot my neighbors! get over here! >> i know i ran into the house. they say i ran past my dad, but i don't even remember seeing him. >> do you remember getting shot? >> i do vaguely remember making the 911 call. >> i've been shot. >> where have you been shot at sir? >> in my arm. >> okay bart, who shot you? >> i don't know. that he went out the back door. i think i said that. >> i pulled up about three houses down, and i pull my weapon, and i start running through the yards to get to the whitaker house. >> reporter: first on the scene, sugar land police officer phil prevost finds 19-year old kevin whitaker dead where he fell, a single bullet in his chest. tricia whitaker also dies of a single gunshot wound soon after she's airlifted to the hospital. incredibly, kent whitaker survives the attack shot in the dhes chest. also wounded, bart makes for a convincing fourth victim. >> where are you in the house right now? >> in the living room. >> okay. do you see the officers, bart? >> yeah. >> i asked him. i said, who are you? who are you? and he said, i'm bart. he said, i live here. this is my house. so i figured he belonged there and said, where's the bad guy? >> can you tell me anything about him at all, bart? did he sound black, white, hispanic? >> maybe black. >> you had yourself shot as part of this plan. was that your idea? >> yeah. it was to distance me from the guilt. >> so you were trying to throw the cops off, in your mind. >> yeah. >> reporter: and it works like a charm. >> the crime scene that i was investigating was a burglary gone bad where the victims were shot by the suspect, and the suspect fled the scene. >> reporter: homicide sergeant marshall slot thinks he's looking for a burglar with bad timing. >> we called out tracking dogs that night to -- in an attempt to track the shooter. >> reporter: the dogs pick up a scent in the house and follow it outside to a dead end. sergeant slot scans the crime scene for anything that might lead him to the killer. he finds drawers pulled open as if by a burglar. a gun safe, pried open. four spent shell casings, and on the kitchen floor, a 9mm handgun with four bullets missing from its clip. investigators find no suspect fingerprints at the scene. they take the gun back to the crime lab for a closer look. >> initially it was processed for latent fingerprints. >> reporter: investigator max hunter carefully tests the weapon and makes a hopeful discovery. >> a partial latent fingerprint was developed on the left side of the slide. it was a partial palm print, but, that palm print did not have enough information in it. we couldn't identify it to any one particular person. >> reporter: tracking dogs identify the shooter's scent on the gun, but dna analysis comes back negative. it seems the killer made a clean getaway. >> it seemed like every piece of evidence that we collected, we ran into dead ends left and right. >> reporter: back to square one. sergeant slot and his partner detective, billy baugh go to the hospital to interview the survivors, kent and bart whitaker. >> they were in separate rooms. so we first went to kent whitaker. kent seemed somewhat at peace. he was obviously upset, but not crying, but he very much demanded that we catch who was responsible for committing this crime. >> reporter: lying in his hospital bed, kent whitaker is torn between emotional extremes. he wants revenge, but he also prays, asking god to give him the strength to do the impossible, and forgive whoever was responsible. >> and the moment that i did ask him to help me forgive, the strangest thing happened. this warm glow flowed over me just instantly, and i looked at my heart, and i realized that that desire for revenge had gone. >> reporter: the thought that it might be his own son he would need to forgive was the furthest thing from kent whitaker's mind. >> when he told me that he had forgiven the shooter i was shouting inside, well, what if that's my fault, and i -- of course i didn't have the courage to say anything at the time. how do you face that? i don't know how to face that. hiding it all from everybody else was sort of like hiding it from myself also. there's also the fear of this place, you know. >> reporter: all of sugar land seems stricken with grief and outrage. more than a thousand mourners, including kent and bart, attend the funeral for tricia and kevin. at the whitaker family home, it's a media circus. >> get away from me! >> reporter: with the investigation hitting dead ends bart has good reason to believe he'd gotten away with murder, but when we come back, the huge secret he couldn't allow his family to discover? >> how could he be so stupid? i just read him the riot act about how if he had been telling the truth he would not be a suspect. & applause] muhammad: i'm going to become champion of the universe! muhammad: me with my beautiful, colorful personality. muhammad: i'm good looking, clean living, cultured, muhammad: and i am modest. 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>> there were some things that stuck out in our minds as being odd, but nothing that we could really hang our hat on to say, this is not what it appears. >> reporter: to sergeant marshall slot the signs of burglary didn't seem quite right. >> the drawers being pulled out like they were and not rifled through was not typical of a burglary scene. >> reporter: nor was the fact that the only thing missing from the house was bart's cell phone. >> and the burglar leaves the gun, leaves all the electronics, but takes a cell phone that we couldn't find in the scene. that was a real oddity that stuck out in everybody's mind. >> reporter: it's the little details that can be the undoing of one who would devise the perfect crime. the first clues for police arise out of the whitakers' last supper. it was a celebration of bart's announcement that he had just graduated from sam houston state university, but -- >> bart whitaker had not graduated from sam houston state. >> reporter: a tiny imperfection in bart's plot -- that became a big crack. >> he had not even been attending the university. he was listed in their records as a freshman on academic probation. >> reporter: in sergeant slot's mind, now bart is a person of interest. >> at the time you were celebrating this are you enrolled in college? >> i don't even remember. i don't think so. >> you weren't graduating from college? >> certainly not. no. >> reporter: bart lying to his parents about attending school when in fact he was hanging out in a townhouse they had given him as a present. >> we took that information immediately and went to kent whitaker first with it. >> reporter: kent is blindsided by his son's lie. >> i realized -- how could he be so stupid? i was so mad at him. i got in a wheelchair and wheeled down to his room and i just read him the riot act about how if he had been telling the truth he would not be a suspect. >> reporter: he may be a proven liar, but there's still no proof that bart is a scheming killer. but then a police officer raises a big red flag when he remembers a call to this house two years earlier. >> trish and i were awakened by a phone call from the sugar land police department telling us that waco police had contacted them that bart was on his way down here to kill us. it was something that a friend overheard bart talking to his roommate about and they concluded that it was a misunderstanding. >> reporter: misunderstanding or not in light of the murders it is significant to sergeant slot. >> we've got the burglary scene that just doesn't look right. we now know that the son is not graduating from sam houston. >> reporter: and now a prior instance of an alleged plot by bart whitaker to kill his family. >> all those little pieces set off bells and whistles in our heads -- just thinking, "we need to start looking at the son." >> reporter: they warn bart's father who refuses to believe that his son might be involved. >> i didn't believe it for a minute. no. >> 57:00 -- 7:54 p.m. >> reporter: indeed, sergeant slot was has a little more than a hunch about bart and a lot of questions. >> how might he have orchestrated this? who might he have talked to to get this done? was this something where he was planning for a big jackpot, a payout, somehow? >> officer dubose is going to be playing the part of the suspect. >> reporter: so sergeant slot returns to the whitakers' home for a vote reenactment of the murders with the two survivors, in identical arm slings. >> i hear "bang!" and the next thing i realize is that i'm lying down like this. >> reporter: first with kent -- and then bart. >> i got shot and i fell back into the couch and onto the floor. >> there were no other witnesses. so my only two sources of information, one of them is the father of the primary suspect. one of them is the primary suspect. so that was a juggling act. >> reporter: then a huge break from an mystery man who walks into the police station one night. adam hipp, a bank teller who went to high school with bart. >> and then he dropped some bombs on me as far as, hey, bart has contacted me before and asked me about making plans to kill his family. his father, his mother and his brother. >> reporter: adam hipp claims bart tried to recruit him as a shooter in an earlier murder plot. >> one of the plans that he laid out to me that he and bart had discussed was the exact mirror image of the actual crime scene. >> reporter: sergeant slot decides to hatch a plot of his own. he enlists adam hipp to trick his friend, bart, on a trapped phone line. >> he told me how your mom and brother were killed and how your dad and you were shot. all that was very similar to what one of our plans was. >> adam, stop saying "our plan." >> okay. >> stop saying that. >> all right. >> i was very, very, very afraid of what he had to say. >> reporter: on the phone tap bart agrees to pay adam $20,000 in hush money. >> you'll pay at least $20,000? >> yeah. >> all right, we'll work out the details. >> reporter: using a courier service he sends hipp a $250 down payment, but then he does something brazen, signing the waybill with the name of a murderer borrowed from a hollywood movie. >> anyone could have worked for soze that was his power. >> reporter: kaiser soze, played by kevin spacey, is the criminal mastermind in the hit film the "usual suspects." >> latent fingerprints, that's what all those markers are. every one of them on the package that was identified came back to bart whitaker. >> reporter: now, the police know they must warn kent whitaker about his son. >> we feel wholeheartedly that he is responsible for this and that you are living with a murderer. >> reporter: but, to protect the investigation sergeant slot gives no details to kent whitaker. >> i knew they couldn't show their whole deck of cards, but they could at least tell me something if they wanted me to believe them. >> kent's response to me was, "you guys are either way wrong, or my son's a monster." >> reporter: despite the warning, kent lets bart move back home and for the next several months bart spends every free moment with his father, playing the perfect son, studying the bible. >> he appeared as if he was really listening. and i told him, "bart, i can't read your heart. you're either zero percent responsible or a hundred percent responsible. the point is that i love you. god has allowed me to forgive everyone involved." >> he truly forgave the person that did this. i mean, he was the first real christian that i'd ever met that really did what jesus christ told him to do. >> reporter: he asked you point blank, "did you do it, bart?" >> yeah. >> reporter: and you said, "no, dad." >> yeah, i did. >> reporter: even though he was going to forgive you. >> yeah, but it's not that simple. i didn't want to cause that pain on me primarily and on anyone else, secondarily. so, i just was weak. i was a coward. >> he was lying to everybody, he was fooling everybody. >> he did not move out of the home. and, it was very soon after that -- bart went missing. >> reporter: seven months after the murders, bart's abandoned suv is found engine running outside a houston apartment complex. >> and it was crushing because up until then, there was at least one member of my family that was still here. and now he's gone. >> reporter: but then a mystery man appears with evidence that would crack the case. stay with us. and you look amazingly comfortable. when your v-neck looks more like a u-neck.., that's when you know, it's half-washed, add downy to keep your collars from stretching, unlike detergent alone, downy conditions to smooth and strengthen fibers. so next time don't half-wash it. downy and it's done. proud partner of the olympic winter games. discover card. i justis this for real?match, yep. we match all the cash back new cardmembers earn at the end of their first year, automatically. whoo! i got my money! hard to contain yourself, isn't it? 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"look! i brought you flowers!" i thought he was so handsome and -- i don't know -- mysterious. >> reporter: she brings her new boyfriend home to meet her parents. he's an immediate hit. her father, homero, even hires him to work at the family's furniture store. >> translator: i ended up loving him like a son. very, very much. ♪ >> reporter: sindy lu knows nothing of her boyfriend's true identity. but one night she gets a terrifying glimpse. it's what he says while consoling her after she smashes her guitar during an argument with her mother. >> translator: he said, "no, relax. let's fix things." he said, "don't be angry at your parents. if you want we can kill them." so i told him "no, but it's not a big deal. and that's the only time i felt a bit of fear, but i know maybe he said that so i would calm down, or to get me to laugh. >> reporter: but no one was laughing. certainly not back in texas, where even kent whitaker was now beginning to believe the worst. >> when he ran away it kinda kicked the third leg out of the stool, that he must actually have been involved. by that point in time i'm thinking it's pretty hard for me to extend any potential arguments against it. >> reporter: but investigators still had no physical evidence, no clue who fired the murder weapon, and no idea what happened to bart whitaker. >> i had nowhere to look for him and no leads to follow up on to try and find him. so that was disappointing at times. >> reporter: the investigation is cold, until a big break from two men who knew bart while he was pretending to be a college student. >> almost two years after the crime occurred, steven champagne called me. >> steven champagne was a marine in 2005, but back in 2003 when the murders occurred, he was a bartender. he worked with bart whitaker at the country club up near lake conroe. >> reporter: now champagne was pouring out secrets about himself, and bart's roommate back then named chris brashear, two aimless guys at the time who were ripe for a payday. bart promised them if they'd help him pull off an outrageous scheme. >> and when they came in the house chris was to shoot 'em all. >> that was absolutely the break we needed. >> reporter: champagne gives up the entire story of what happened on the night of december 10, 2003. >> what was bart's part in the plan? >> he pretty much set it all up. >> how did you know which restaurant? >> bart had told me before they left. >> reporter: as the whitakers unknowingly celebrate bart's bogus college graduation at a popular cajun restaurant, steve champagne watches from the parking lot. meanwhile, bart's roommate chris brashear hides in bart's suv outside the whitaker home. >> at that point chris got out of the vehicle and entered the house with the key and the alarm code. >> did you see them leave pappadeaux? >> well, yeah. so then i pretty much followed them home. they pulled in the driveway and i just kept going just around the block, you know, one block over. and then in a minute, chris came walking, like, out to the car, got in the backseat. he said bart's brother had walked in first. and, when chris shot him -- he said before he shot him he thought he smiled. and then chris shot his mom and then shot bart's dad in the shoulder. and then, he acted like he wrestled around with bart and shot bart in the shoulder. >> you could characterize that interview as chilling. i don't think there's anyone who could watch that and not wonder how a person could be so cold. >> reporter: unaware of champagne's confession, chris brashear agrees to an interview -- but quickly becomes very uncomfortable. >> i'm just gonna go. is that all right? >> yeah. there's the door. >> reporter: so sergeant slot, steven champagne's confession yields the one thing that links this trio to the crime. he mentions a key piece of evidence that only the police knew about -- a single glove dropped by the shooter, found beside bart's suv. >> he knew about the missing glove. and, obviously, we had this glove in evidence already. so everything fit together just based on one small piece of evidence. >> reporter: but sergeant slot still has no physical evidence to link bart to the murders -- until now. >> steven champagne explained to me that he and chris brashear had thrown items from the crime scene into a bag and thrown that off of a bridge that runs over lake conroe, near bart's town home in willis. >> reporter: down below, a dive team discovers a duffel bag. in the soggy bag, a treasure trove of decomposing evidence. it's a windfall for crime lab investigator max hunter, beginning with an innocuous-looking plastic water bottle. >> you just go around the rim of the bottle. >> reporter: and even after two years in the bottom of a lake -- >> they were able to obtain a dna profile. from that swab, and that dna profile matched the dna profile for chris brashear. >> reporter: among the other items in the bag -- a rare brand of ammunition identical to the fatal bullets. a glove that matches the one found at the crime scene. a pry tool that matches the marks on the whitakers safe. and a badly damaged cell phone. a lab in england identifies bart whitaker as the owner. finally, sergeant slot has the physical evidence he needs to link bart to the murders. >> this is definitely when we said, "we've got it." >> reporter: but where is bart whitaker? sergeant slot obtains an arrest warrant, but he does not know that bart -- now known as rudy rios -- is hiding in mexico. and then, the biggest break of all -- a phone call from the real rudy rios -- when we come back. in your noise cancelling trheadphones?ry maybe not. maybe you could trust you won't be next to a loud eater. 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(silence) ♪ how's he getting the client loves him. but anyone can say, "get 4 lines of unlimited data for $100/mo, plus up to 4 free lg fortunes when you switch." but he's got that hair. i am hair! come here, little buddy. smile. you're on cricket. the unique formula with nourishing almond oil leaves skin smoother moisturized for 24 hours. enjoy smoother skin and now try new oil infused lotions moisturize with indulging scents oh! there's one.a "the sea cow"" manatees in novelty ts? surprising. what's "come at me bro?" it's something you say to a friend. what's not surprising? how much money matt saved by switching to geico. fifteen minutes could save you fifteen percent or more. >> reporter: how does a seemingly normal, fun-loving boy raised in a beautiful home by caring parents -- >> what is that? whoa. >> reporter: -- turn into a murderer who would ambush his own family and even take a bullet in the arm to make himself look like a victim? >> that whole plot, it was always a -- i hesitate to use the word "game" because people love to take what i say and twist it. but, it was sort of like a game of chicken between me and the other guys. who flinches? i never really expected chris to pull that trigger. >> did you feel any guilt? did you feel any shame? >> i wasn't feeling much of anything but yeah, it was there. it was just on a level that i wasn't paying any attention to. >> he seems singularly without remorse and without even the beginnings of remorse. >> reporter: a classic sociopath says psychiatrist dr. edward hallowell, of the hallowell centers in new york and boston. >> i was struck in the interview that he showed almost no emotion. here's this young man who's done about the worst thing a person could do and it's as if he's talking about the weather. >> reporter: that observation is confirmed in the confession of getaway driver, steve champagne. >> did you ever see any signs of remorse in bart? >> no. >> reporter: and it gets worse. champagne says bart also talked about wanting to finish the job and kill his father. >> i'd love to have an outside perspective about why i think certain things. >> what if the diagnosis is that you are a sociopath? >> well, then i am what i am. >> reporter: dr. hallowell has never examined bart whitaker, but also sees a narcissistic personality. >> it's an extremely dangerous combination. extremely dangerous, because you have no guide. you have no internal brakes. and you have this tremendous feeling of emptiness, so you want stimulation. >> i hate myself. i can't imagine i'm a narcissist. >> you want to somehow feel alive. and the normal things that make people feel alive, love, attachment, bonding -- that's all gone. i mean having these fantasies about murdering your family. he had to go to that length to feel alive. >> reporter: finally in september, 2005, the climax of unsolicited witnesses and police work, there is good luck that comes in the form of a phone call. >> the real rudy rios comes forward. this is the guy that bart whitaker has been impersonating. >> i know where he is at because it's my family that's taking care of him. >> reporter: a bus-boy at the country club where bart worked, rudy rios tells police he sold his identity to bart and helped him escape to mexico for a couple of thousand dollars. now he's prepared to sell-out his friend for a $10,000 reward from police. >> but, if there's a reward, you know, i don't care. i'll turn his ass in. >> i'm thinking, "this is the break we need." when rudy rios gave me this information and it seemed to check out, i was ecstatic. >> reporter: bart whitaker is arrested in mexico. and, on the road back to sugar land, sgt. slot has only one unanswered question for his prisoner. >> how did you get all of these people to do such horrible things for you? and bart responded to me that it was easy. all he had to do was give them what they wanted. >> what was y'all's benefit for doing this? >> bart said his family was worth a lot of money. he said he would give us millions of dollars. >> that was motivation for them. it was never about that for me. i didn't care about money. i had plenty of it. >> he had this amazing ability to inspire, persuade, cajole. to do something absolutely not in their self-interest. i mean, to do something crazy! >> you planned to have your family killed not once, right? >> i believe there were three separate occasions. >> but, why bart? this is the question everyone wants to know. why? >> i wanted revenge for being alive, and i blamed them for that. i blamed them for who i was instead of blaming me. >> you blamed them even though the evidence points out that they really loved you and nurtured you and tried to give you everything that they could possibly give you. >> yeah, but we really didn't connect on that level. >> i think he really believed that who we were loving was someone that didn't exist and that he was hiding behind a mask so that we would never find that out. >> reporter: next, as the last 40 minutes of bart's life tick down -- yet another twist of fate. with big dreams... we came with big appetites. with expedia one click gives you access to discounts on thousands of hotels, cars and things to do. like the garland hotel for 40% off. everything you need to go. expedia tto find your balance!s everything you need plus an extra 20% off eat healthier with an air fryer get moving with new active apparel. and sleep well with cuddl duds. you'll get kohl's cash too! and yes2you members earn triple points! kohl's. for mild-to-moderate eczema? it can be used almost everywhere on almost everybody. the leg of this little guy? the arm of an arm wrestler? the face of a fairy? eucrisa is a prescription eczema ointment for ages 2 and up. it blocks overactive pde4 enzymes within your skin. and it's steroid-free. do not use if you are allergic to eucrisa or its ingredients. allergic reactions may occur at or near the application site. the most common side effect is application site pain. ask your doctor about eucrisa. ♪ baby, ♪ i'm losing myust memind just a little ♪♪ ♪ so, why don't you just meet me in the middle ♪ what can i do for you? >> nothing. >> reporter: with father and son both back in texas, jailhouse phone calls confirm kent's unwavering support of bart as he awaits trial. >> well, just hang in there. keep calling. >> i love you. >> i love you too. i walk in this room with the bullet proof glass between us and there's bart. and he said, "dad, i'm so sorry. this is all my fault." and it was at that point i realized he was saying, "i did it, i'm sorry, i want to confess." >> reporter: he believes his son has truly changed and repented and now feels genuine remorse. >> he's an amazing man. and, whether or not i'm a person incapable of love, i am a person capable of feeling a very deep respect for that man. i love him to death. >> forgiveness is absolutely critical if you want to heal from your loss. if you don't forgive, you're basically shackling yourself to the event you want to grow past. >> reporter: bart, how do you feel about your mother? >> i wish i could talk to her now. i'd tell her i'm sorry. i'd like to redo that whole relationship from start to finish and be able to really appreciate what she was sending me. if we could all live twice. >> reporter: two years after his arrest. >> a jury convicts bart whitaker of the murders of his mother tricia and his younger brother kevin, and sentences him to death. >> if victims' rights means anything at all it should mean something even when the victim is requesting mercy and not just when the victim is requesting vengeance. >> reporter: earlier this week, kent took his fight to its final round, the texas board of pardons and paroles. the prosecutor unmoved. the father didn't want us to seek the death penalty. and he's the victim. however, i don't represent the victims per se. i represent the state of texas. >> reporter: kent, who has now spent more than a decade making the weekly drive to death row, asked his son be given a life sentence with no chance of parole. the odds were stacked against him. since 1982, there have only been three commutations so close to an execution. but then -- >> now to our top story tonight, a death row fight for life. >> reporter: a phone call to kent's lawyer with news beyond his best hopes. a unanimous vote to recommend clemency. >> a recommendation for clemency. >> oh, my god. >> it's bizarre. it's surreal. and we're just so encouraged that the system worked here. >> reporter: but that controversial decision isn't the final word. would governor greg abbott accept the board's recommendation? kent goes to the governors office, but isn't able to meet anyone in person. >> he is a very law and order kind of guy and believes in the death penalty. there's a lot of speculation here and i don't think anybody knows what the governor's going to do. >> reporter: for the longest time, governor abbott did nothing. bart is a dead man walking. he is taken to the death house. prepped for the execution. bart speaks to a chaplain. a last meal is served, chicken enchiladas. and then -- >> this just coming into our ears. we understand governor abbott has commuted the sentence of bart. >> reporter: and then, with barely 40 minutes to spare, for the first time in more than a decade, a condemned man gets clemency. >> it was overwhelming. i'm so grateful, so grateful. test test bittersweet journey has come to a close. >> i may have actually have the opportunity to be in the same room with him touch him, shake r past into a future together. >> down the street. ♪ >> so if you had been the governor, what would you do?nd twitter. >> in the meantime, that is 2010 twn for tonight. i'm david muir. >> i'm elizabeth vargas. for everybody at abc news >> coming up on "action news" tonight, the slow recovery along a fire ravagerred block in old city. and organic foods in consumer reports. and organic foods in consumer reports. that's next. (vo) you can pass down a subaru forester. but you get to keep the memories. love.bruary 28th. "action news," delaware valley's leading news program with jim gardner. >> earlier this week people were wearing shirt sleeves enjoying spring weather. not tonight. it's