w, an all new "dateline" mystery. this one also begins in a quiet neighborhood stunned by sudden tragedy.l. >> i was reeling from shock that my parents were gone. >> a devoted couple killed in hey shared with a museum's worth of collectibles. >> he was big into the civil war. guns, coins of all kinds.onnection between the memorabilia and the murder? >> who was going to benefit from these deaths?e only child. >> the sole heir? >> the sole heir.ong the treasures, a clue pointing to a most surprising and calculating killer.

>> here is dennis murphy with ctor." travels tea ake you to the ozarks, perhaps you have fishing on mind. that would have directed you to this modest home in springfield, missouri. that's a shame, because it was e ious sity shop well worth seeing. valuable stuff everywhere the eye landed.ct just so. >> everything from coins to arrowheads. he had probabloks. >> he's big into gold and silver, gem. >> bayonets from world war i, lead cannon.ut did these collectors have a less discerning eye when it came to sizing up people? and that go towards explaining l in the house

>> i said, he's off in some way. i don't know. he could be a psychopath or something. scares me. >> on april 30th, 2014, did they fall prey to someone they believed could be trusted?owered to the ground. and i started crying and screaming.h, such good people, why? >> springfield, missouri is called the queen of the ozarks. a church going, neighborly city e with good colleges. gary tyrell grew up poor on a farm not far away and knew early on that his adult life would be ion. teaching kids in his classrooms by day. the history book in his lap at night. he and his kids.

young of a brain cancer.kept the house mainly, and sold i have an sold avon products part-time. they designed their house themselves. life in missouri was good for the two.ved each other very much. >> daughter jessica remembers how extraordinarily close her ined at the hip. >> if my dad went shopping, my home went with her. they talked on the phone several times a day if they were apart.ere for the ages. >> yes. yes. >> personalities? gary >> he was a jolly man, kind of like a santa claus. >> jan, a little more reserved. >> it might take a little bit more to know her.up to you, she was very alive. >> when gary retired as a beloved assistant school he suddenly had all the time in the world to visit civil war battlefields, markets, and pore

but there was a lucrative obsession over memorabilia. gary's brother, larry tyrell. >> he constantly collected d sold trinkets. >> and did well at it? >> gary was a good businessman.he gold and silver went into one of the five saves in fe s safes were in the house.d indian jewelry, quality pieces that he loved. >> what was his favorite piece?lrus tusks. he loved those. >> they were rare, each worth around $10,000. >> how would he find these >> i'm not really sure. they did go to flea markets and garage sales and things like that. any time i would ask him, you know, where did you get this, he oh, in my travels.

one of the family when he and jessica got engaged.rs the walrus tusks as well as all the other unusual items in the tyrell home. >> there was so much stuff in , yet it was immaculate. it was like an off beat museum. >> jessica and jason lived way in oklahoma city. but jessica spoke with or texted her parents several times a day. but that all changed on may 1st.my mom on my way to work, like i always do. and she didn't answer. so i thought, well, maybe she's hroom, maybe she's outside. and i called back and i still did not reach her. >> by noon, jessica says she still couldn't reach her.pringfield police and asked them to go by the house. >> when the officer did that, what did he report back to you?seemed out of place. they couldn't see anything inside the house. all the doors were secure.

entry or that anything appeared to be out of place. >> the officer had no cause to force his way into the house, and left.a says she was still worried. so she and jason jumped in their car to make the five-hour drive to springfield.the house around 7:00 p.m. >> as we were coming around the corner to the house, i hit the garage door button.heir cars were in the garage. >> that was bad news for you. >> yes. >> what did that imply? >> that there was something terribly wrong.essica called 911 without ever going past the garage into the house. two officers arrived within minutes.hey entered the home. and then another officer arrived, and then another, and then another, and then another.iting outside. >> i'm waiting outside. >> no one said a word to jessica and jason.

>> i kind of grabbed on to the officer and i said, what is going on? why are they calling for crime scene tape?he kind of, you know, held me and said, i don't know what's going on. all i know is there are two people in the house that are >> chilling words outside the tyrells' house. but they were nothing compared ators would find inside. when we come back -- >> personal anger. >> it definitely seemed to be ew tal utal. >> ity involved.

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>> reporter: as darkness closed in on springfield, missouri, the police to check on her parents, was now being told two bodies e her parents' home. they didn't identify them but jessica says she knew it could

screaming.t was -- it was my worst fear. >> reporter: her fiance, jason, was by her side, trying to ole her. >> she was -- beyond upset. she kept saying, "i'm sorry, mom. i'm sorry, mom." >> i had no details -- had no idea what had happened. >> i'm thinking, "this is horrible." it's like carbon monoxide, something along -- >> something. but not benign, but something explainable? >> reporter: but inside, officers quickly grasped the cold, stomach-churning truth. jan and gary's deaths were not accidental.was gonna be a long investigation. >> reporter: detective neal mcamis was one the first detectives on the scene.ntered the home through the garage door and saw gary first. >> we could see that there was a deceased male in the hallway of the home.ts were pulled down. what did you make of that?

the only thing that -- we could s trying to get away from somebody, that they're grabbing a hold of him. >> reporter: or was the killer rifling his pockets for something? a key, maybe? in gary's office downstairs, the detective saw jan. >> she was on the ground. she was lying face down. was obvious that there was severe trauma to the back of her head. >> reporter: so was this a violent home invasion? more than a half a million dollars worth of valuables in the house for the grabbing, so a botched robbery was a likely scenario. garage, police did find strange marks and scratches on a tornado shelter that was also used as a safe. had -- tried to pry the lock open. there were some marks that -- that were by the -- the lock on the on the door of the tornado shelter. >> they didn't get inside. >> and it did not appe. >> but that would suggest somebody's looking for something. >> yes. >> reporter: but if robbery was ller had left the oddball museum strangely intact.

of place. and the nature of the was shot as well as beaten, spoke volumes to the prosecutor assigned to the case, todd meyers.e an element of personal anger in this thing, todd. this close quarter killing of somebody with -- with a weapon in your hand.itely seemed to be a personal-type killing, just the brutality involved. >> reporter: investigators gary were likely killed the night before. but search as they might for the murder weapons, the gun and the bludgeoning instrument. empty handed. but they did recover some unusual evidence. >> around jan's body there were small white flakes of a substance that were obviously either from the murder weapon or on the murderer's body. there were similar flakes found ead. >> reporter: so they bagged them and sent them off for testing.

recovered something else that al piece of evidence -- a discarded latex glove. >> so a latex glove on the floor jumped out at you. >> totally outta place.alking with everybody, that there is no way that gary or jan would have left that glove there. it was right in the middle of erybody to see. >> reporter: did it belong to the victims or the killer? no one knew. >> so it's collected. you don't know what it means. >> we don't know what it means.cted. sent to the highway patrol crime lab. >> reporter: they had no idea. no working theory yet of why themurdered. but they did have a sequence that made sense as to the order of deaths. >> it is hard to believe that is shot upstairs if jan is still -- fully functioning and mobile that she would not have called 911, would not have tried to intervene in some way. >> speculation, but common sense victim. >> she's the first victim. yes. >> she's bludgeoned to death downstairs. gary arrives at some point later.

the killer is waiting for him.t appears that she would have been the first to have died. >> reporter: a big question early on for detectives was understanding their crime scene. how did the killer gain entry to >> there were no signs of forced entry. >> windows haven't been forced. the doors are all intact. how did the killer get in? >> there are only two ways the e gotten in. one would be to have -- their own access device, whether it's a key, a garage door opener, some way that would open the doors up.pon leaving, be able to lock it that way. or, to have been let into the house by either gary or jan.t didn't appear to the cops to be a random home invasion -- but rather that the killer or killers had been le knew. was it a person gary encountered in his antiquing travels? or -- terrible to think about it -- was the perpetrator ser to home.

>> i was shocked -- really nfused, and baffled. be. coming up -- who had a motivate to kill the tyrells? investigators have at least one idea.rson who could benefit from this crime in terms of getting money. >> she's the only child of ll to do with a lot that's going to be left to her. >> when "dateline" continues. ble, so embrace it! head and shoulders. live flake free for life your own tour of italy at olive garden, starting at $12.99. choose 3 of 10 favorites to enjoy on one plate. and breadsticks.

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>> reporter: two dead.

downstairs.d shot twice upstairs. and springfield police had determined this was no random break-in gone wrong. 's modest home was filled with valuable items. and yet, at first glance, nothing appeared to have been taken.upposition was their killer was likely someone close to them. and no one was closer than daughter jessica. >> she is the person who could benefit here frms of getting money. >> she had the most to gain. she's the only child and -- who had -- from parents that are with a lot that's gonna be left to her. >> so, she's gonna be questioned hard. >> yes. >> reporter: so that night, fiancee jason down to the station to answer a few questions. the cops didn't let on they weret just as grieving relatives. but also as potential suspects. going to take a few notes, obviously, as we're talking. so don't let that, uh, don't let that bother you. >> reporter: the interviewer withheld details about the crime scene.

to see if a subject knows more than they should. he even threw out a theory that wasn't true - murder suicide.ings we have to look at is as to whether or not that one of them would've injured the other and then maybe themselves. d to go with it. >> do you think that's a possibility? >> my dad, since his mom died, has been super depressed and has made comments. and my mom called the doctor's office, and i told her if he did -- if he said something stupid before, again, that she needed to call the police.leep ] away from him and call the police. >> reporter: and as they continued talking, police had another reason to be suspicious she'd driven 5 hours to check on her parents. then didn't go inside the house. >> and you wonder why she would do that? >> yes. that commit a crime or know a crime that's been committed, you know, they don't wanna see -- the bodies in there so they call somebody else.ectives pressed

that day -- what they did or did not do at the scene. had they tampered with that in the garage. >> you guys didn't do anything to try to get inside? >> oh no, no, no, no, no, no. i mean i pushed my hand on the handle, it was locked and that was it., "are we looking at maybe -- having a situation here where we gotta call a lawyer or be careful say?" >> i did, a little bit. >> reporter: but neither jason nor jessica asked for a lawyer atective more detail about what was in that tornado shelter that had been tampered with. >> the safe room was full of gold, and silver, and gold bars and i don't even know -- >> we actually don't know what >> i don't, i don't -- i mean he has books that are signed by presidents. he has indian peace medals. >> reporter: for investigators, test..... >> how are you gonna hold up? are you gonna give answers that we can go back and verify? are you going to respond appropriately-- to sweat them? >> yeah, that was the detective's intent -- to the degree of just trying to make

>> reporter: so had they passed vestigators test? detectives let them go but held onto jessica's car to test it for potential evidence. >> why did they have a reason to look in idn't really know. i assumed it was just because my car was there. >> reporter: now jessica had to call family and friends to tell out her parents. her uncle larry, her father's brother, was at his law office when he got the call. >> she said that--gone. i said, "what do you mean? are they out of town?" and she said, "no, they're-- they're deceased."d on the floor. >> you were a mess. >> i was a mess. the unknown was terrifying -- because i didn't know what had happened. larry wasn't shocked or outraged to learn his niece was being looked at as a t. he was, after all, a criminal defense attorney and former prosecutor. >> i knew she had to be eliminated. i understood that-- due to the s the only child. i mean -- she just had to be

could move on. the case did keep moving--- but after a full week of investigating, the daughter and her fiance were not. rather, detectives called them back to the station, this time interviewed separately. jason first. cops by now had figured out that the murders took place the nights were discovered---so where exactly were he and jessica then? to the pizza hut on -- i don't know, probably 5:30 or something like that, then came back home, and stayed home. >> reporter: home, five hours oklahoma city. >> do you remember how you paid for the pizza hut stuff? >> i'm sure it's on my card. >> credit card. >> i'm sure it's on my card. >> reporter: then, right to the point.ou have any reason to wanna harm gary or jan? >> not at all. >> didn't do anything to hurt them? >> no sir. >> didn't go into the house? anything like that? everything you're telling me is the truth? >> reporter: next jessica was in the chair, answering questions about her relationship with her parents.

bills, cars? they pay my at&t bill for my cell phone. they pay my car insurance.k that's it. >> i'm just gonna ask. did you have any ill feelings toward your folks? anything that you would have for? any reason to want to harm them or anything like that -- >> no. my parents were my life. >> to better, better yion or anything like that? >> no. i mean, if i needed something, all i had to do was call and ask. >> so you're a suspect-- >> --in your parents' double homicide? >> yes. yes. >> how do you deal with that? you haven't even buried them >> i wasn't really dealing with it. it was more just going through, and saying -- i, you know, i didn't do it.ice asked both jessica and jason for dna samples, then set out to verify their alibis. >> my boss and i took a trip to d we went to

spoke with-- fellow employees. with jessica's boss.he pizza hut to see if we could see some-- surveillance video. >> reporter: would it all check out? or would an unexpected lead sendn in a new direction? >> this was a huge bingo moment. coming up -- gary's best friend offers detectives some e says he saw on gary's phone. >> some guy that was asking for money. badly enough to kill? breo won't replace a rescue inhaler for sudden breathing problems. ays to help improve breathing for a full 24

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an early spring day jessica tyrrell had planned to go wedding dress shopping >> era un sa bado de s instead, burying both her parents. >> i basically just cried, and -- was constantly ill. through at that point is just unfathomable. i mean, she is just broken at this point.

was held at a high school in thechool district where gary worked for 30 years. nancy littrell was a school board secretary.ust so hard to believe that something so bad could happen in springfield and double unbelief dy you know. my heart has just gone out for poor jessica. >> reporter: the outpouring of was a huge comfort to jessica at a time when she needed it most. word had gotten out that cops her. >> yeah, lots of rumors that i did it. >> that's tough to go out every day and say, "i didn't kill my >> right. and it got very tiring to hear, you know, someone say, "well, you need to look at the daughter. she did it. to gain." >> and they did take a hard look. >> yes, they did. >> they think the daughter has killed him in order to get the money, that she's in cahoots with her fiancee.l? >> you might not have believed it, or your circle of people

>> my circle -- my circle was not believing that. >> reporter: and behind the nd prosecutors had come to the same conclusion -- jessica and jason were innocent. >> everything that jessica and the police, the police were able to corroborate and verify. >> and they went through everything. they went through the phone records. the alibi was checked out top to bottom. >> it was. when the dna results came back on the latex glove, neither of them was a match. it belonged to an unknown male.lief for you? >> yes, i mean, we knew we didn't do it, so, i mean, it was, like, "okay, well, now you need to find who did it." >> reporter: athey could help the investigation with their own amateur sleuthing. for instance, when jason went back to jessica's parents' houserst time, he noticed something was missing. >> there was a display of little ivory pieces and multiple walrusknow, kind of engraved art type things. and they had been moved. >> walrus tusk, jason. are we talking about like -- like so? >>

right. the larger one was not where it was supposed to be, and the other one was not there at all. >> reporter: jason told police f gary's prized tusks could be the murder weapon, the source of those mysterious white flakes.a a noticed something, too. at her dad's desk where he sorted coins. >> he kept them around his desk in coffee cans, and -- bags -- and he would be sorting them, or -- organizing them. >> reporter: and a container with what would have looked liketer change was missing -- it's actual value -- around $20,000, according to her dad's records. the killer would have known the real value only if he moved in the same antique circles as gary. at least that's what the brother suspected. had went to buy some gold or silver and that someone had set him up and that had someone follow him home and got the drop on him or jan and -- had robbed him and killed him. >> it sounds very plausible.g worry i had.

into gary's business dealings, no potential suspects emerged.ny idea how wealthy they really were. >> they did not show that type of wealth to people. it was always kept very quiet.he would interact with, as far as selling the gold were always very reputable-type people. >> reporter: and because there ome, larry offered up the very limited list of people who had access to the house, a handful of local contractors.were -- asking the garden guy, and the cabinet maker, whoever might have been in that house from larry's list of people to give dna. >> right. officers were reaching out to others in the couple's inner circle. gary's closest friend was arried father of two, prominent guy in town and former school superintendent.ise thing to do to clean the floors. >> he was handsome. he looked good. he dressed good. when he first came to the

both gary and mark. >> they seemed to get along really well, worked well together.ere friends at school and off of school. >> reporter: so mark went down to the police station to talk tigators. >> all right mr. porter. is it -- it's mark? correct? >> yeah. >> do you mind if i call you mark? >> no, that's good. >> okay.o kind of touch base with you and talk to you a little bit about how you, how you know them, how long you've known them. >> well, gary, since probably he was my assistant superintendent. i was -- i was the superintendent. >> reporter: mark knew a lot about gary's coin business. he'd started dabbling in it as well.tectives details that suggested a fellow collector could have targeted the tyrrells. >> he's got people all over souri that collect for him, and i know he goes to hotels, and meets people and he's -- he runs ads in the paper.ding to mark, gary set up one of those meetings around the time of his

money. >> he was actually going to sellfor cash. it was -- it was actually a buyer who was going to give him $50,000 cash. that's all i know. >> reporter: he also mentioned 'd seen on gary's phone from some other guy. >> gary asked me to read him some of his text messages and there were five in a row from had taught in a class that was asking for money. >> okay. >> and i have no idea -- >> was there a name attached with the text? was it just from a number? >> i can't remember. >> reporter: and remember, gary was shot as well as beaten.en with one of his own guns? >> gary has guns everywhere. gary has guns in -- in every drawer of the house i think. i mean, he likes his guns. he loves guns.eporter: but then, mark gave detectives a detail that took them completely by surprise. >> he was supposed to meet me , uh wednesday, and didn't show. >> reporter: wednesday, the night of the murders. it was the first police were

that night.did the best friend know?coming up, mark gives a detailed account, one that troubles investigators. >> there were several things about that story that raised questions. reveals who he thinks had a motive for murder. >> i know he had some sort of bad financial issue. >> when "dateline" continues.

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r: springfield police were talking to gary's best friend, mark porter, who suggested plenty of theories about why gary was killed. he said gary's money was catnip nds of folks. >> you know people who knew him, if they knew he had money were always asking. >> reporter: then mark revealed something detectives didn't know.y had plans to meet at mcdonalds on the night of the murders. >> and how long do you think you waited on him? >> i waited probably a good, i there probably 7:45. uhm. probably 45 minutes. detective: okay. >> reporter: so the friend said he drove across town to stop by se. >> i went back to the house, knocked on the door, nothing, didn't answer so i thought he had either gone or he had left, cause sometimes, cause he'll leave.nd say, "oh man i forgot, my uhm my bad, i'm, i'm in kansas city," so i had no clue.

detectives that gary had stood o big deal. so he went back to his office at ibm to do some work. >> now, there were several things about that story that raised some questions. >> like?hy would you wait 45 minutes for someone and not pick up your phone and give 'em a call, and say, "hey--". >> what's up?up? did you forget?" >> reporter: but what seemed really strange was that mark porter had just admitted to going to the house the night of the murders, with a story that t ring true. why drive across town if he wasn't all that concerned about his friend missing dinner?a few miles across town to go knock on the door, when his office is across the street, when it doesn't . >> so he puts himself at the house? >> he puts himself at the house >> but with a benign explanation, huh? >> yes. >> reporter: inside the the detective decided it was time for a break. >> give me just a couple seconds i'll go back there and see if there's anything else. can i get

>> no. >> reporter: trying to make including this bit of information. gary's brother had told police that not long ago mark asked gary for a loan put the request in writing and not just a little bit til payday but an ,000 dollars. >> that's the kinda money if you can get it out of your house as a second mortgage maybe you're-- you're lucky. >> right. right. >> what did your father make of der it even for a heartbeat? >> no. not at all. when he was talking to us about it-- he was kinda laughing and i-- i don't know where he thinks i would have this kind of money." >> reporter: strange, since not gary's former boss, have had a nice pension as a former school superintendant, he was currently earning a six ibm. brother larry had suggested mark might have a gambling problem. >> i knew he had some sorta bad financial issue.r: when the detective came back to the room, the tone of the interview had changed completely.

for money yourself?, no. only for uh only uh in trade or buying. >> reporter: suddenly, mark porter was in the hot seat. >> so if i was getting somebody who told me that maybe you had a large gambling debt that you were ask for -- a large gambling debt. >> gary for. >> no. >> for maybe some assistance with? >> no.false? >> yeah, that's not true. >> reporter: he denied asking for the loan said the only time he discussed large sums of money with gary was about a real estate deal. looking for investment, whatever. >> reporter: then detectives asked him the question they'd asked everyone else would he offer up a dna sample? >> all i have is just like a if you're fine to do that while you're here today. >> no i'm gonna wait. >> okay. any particular reason? >> i just i don't know, i don't want to, i don't want to do something and my attorneys say i shouldn't have done that. >> okay. >> why would you not give us a dna sample? >> he's your best friend. we're trying to find his killer.t friend. we're doin' everything we can to try to find who brutally murdered

and you're tellin' us that you're not sure you're gonna mple. >> reporter: the refusal wasn't evidence of mark's guilt so police let him go. ddenly shifted away from the workers at the tyrrell home and toward mark porter. some detectives hit the pavement hile others continued mining other avenues for leads. one cop thought to check a local database of pawn shops to see ifng items from the tyrrell house had been recently sold.them here to r&k coins. >> tell us how your business ended up bein' very important in a murder investigation in springfield. >> yes, sir.was just two days after jan and gary were killed when kelly eddington was working behind his desk and a lked in. >> what were you seein' in him? was he okay? was he normal-- demeanor-- >> he just looked like a me. i didn't,

him at all.of dimes, quarters, 50 cent pieces. when you added up the face value of that stack of money, ho wh-- what was it worth? >> he had $1,200 and $1,210 in face money.own value of the metal itself was worth what? paid him $18,351. >> reporter: $18,351. a lot of money and not far off the value of the coins jessica reported missing from her parents' home. walked in and stacked his coins and you did the transaction, your security cameras caught it all, huh? >> sure did.o who was it? coming up, how an mcdonald's coffee cup was about to blow the case wide open.ard just light up when you hear that? >> i can't even describe the emotion of it.a family learns the truth.

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detectives finally had a major break in the

same amount as the ones taken from the tyrell home had turned up in a local coin shop. e transaction on video. the man certainly looked familiar. but if there was any doubt, he is i.d. >> mark porter. mark edward porter. that's a real license. >> that's him.ut selling a load of coins didn't prove mark porter was guilty of murder. remember, mark also had an coin business. >> his explanation was these were coins he had, it was just aappened to sell them the day after the tyrells were schooled. >> by all appearances a pillar was now a prime suspect in the murders of jan and gary tyrell. >> i never did like the guy. i didn't trust him. something of a

>> gary's brother larry always had a bad feeling about mark.onvinced if mark was the killer, the motive was money. >> i felt he was befriending and grooming my brother so he could is money. i think over a period of time he saw jan as an obstacle.learned detectives were looking at mark, she wasn't surprised. >> she didn't show up at the funeral.uous by his absence? >> it was pretty obvious at that point that there was something going on. >> his former secretary said sher mark porter. ended up quitting her job to get away from him. >> he's off in some way, he opath or something. >> you used that word? >> i did. >> but what bothered police was his lack of cooperation.dn't give dna. he wouldn't take a polygraph.

story about stopping by the tyrell house the night of the murders. talked about making a couple of phone calls to mark and she couldn't get ahold of him, didn't know where she was . >> but police still needed physical evidence.le to match to the lay latex glove found at the scene. >> we had undercover officers surveillance for weeks and weeks and weeks to try to somehow obtain a dna sample from him.bing a sample approved to be more difficult than expected. in all those weeks, officers continued to come up empty. his lunch. they watched him get a to-go cup. they were all excited because able

>> so he knew that you guys had eyes on him?fficult to know what he knew at that time. >> then three months after the murders, an undercover officer to an automobile oil chain shop. >> egging he goes inside. coffee cup he had gotten from mcdonald's. he drinks from the coffee cup. up a casual conversation. >> the suspect and the undercover cop. >> the suspect and the undercover cop.behind the coffee cup. >> police had their sample. in less than 24 hours, they had the results. >> it's confirmed, it's a match.na from the coffee cup and the same at from the latex glove.

>> i can't describe without ll be able to tell the family that we have some news. >> how do you take that? you've got the wrong guy? >> absolutely not. he said, okay. that's all he said. >> jessica was at work.my very good friends were with me. he said, he's been arrested. i remember falling to the floor and just being so overwhelmed he was finally caught. >> even the former secretary who didn't like him was horrified.lieve it. i mean, oh, i thought, no. no. >> investigators went back to told her that her own husband's story put him at the scene of the crime. >> you really need to help us out here.k say he was there? >> at the time they were killed. >> no.

yes, ma'am.ircumstantial. >> and that's exactly what mark porter's defense attorney argued. mark hired one of the best to >> a spotless record, five college degrees, has an reputation. >> at a bond hearing, the defense revealed its strategy. they would argue there was nothing suspicious about mark's inside his best friend's house. he was a regular visitor to the house, he would get with gary, they would put on their gloves the old coins and objects and that's why the glove was there. jurors, it's benign. is that how it works in the realourt room drama? >> potentially, yes. >> what about the suspicious coin sale?

compulsive gambler? did he owe money to people?er any evidence we found that led to that. >> so the case, a potential death penalty one, was when mark hired new attorneys who asked to talk about a plea deal, the prosecution was willing to listen.e we willing to risk? to try to get the death penalty, can we achieve what we need to achieve without the risk of going to trial? >> he could walk.nce of a hung jury and you have to do it all again. or they could come back on a lesser crime.reed. mark porter pleaded guilty to rder and he was sentenced to prison. no eligibility of parole until age 82. >> i'm shocked and sad.relief that mr. porter is finally going to be

rest of his life.very day with what he did. every day he has to think about what he did. and all of tyed. >> you're saying you have to live with remorse, but you haven't seen any sign of remorse. >> that is the only bad part.ll has to sit there. >> today, jessica is doing her best to move on. in february of 2015, she and lly got married. >> we got married on valentine's day. it was a great day.very sad. my parents weren't there. >> larry took his brother's place and walked her down the aisle. >> she asked me to give her away.een my brother's job. >> kind of a bittersweet moment? >> mm-hmm. that's true. i was honored to do it but i t doing it. >> to keep her parents' memory alive, jessica has set up a

home, it's still there, with a loving daughter as caretaker. >> i still feel them there.house. my mom built that house. i grew up there. and so i can't let that go.or this edition of "dateline." we'll see you again friday for at a special time, 9:00, 8:00 central. and of course i'll see you each c nightly news." for all of us at nbc news, good night. to get me into that jock feel. - you are an ex-jockstrap. - ex-jock. - you-- race"... - do you have a favorite jack and karen moment? - [laughs] so many. - how much time do we have? [laughter] announcer: "frasier"...ja in "will & grace." oh, my god, cher? cher! [laughs] who's got the best talk show