return home to make it look like he was home that night to make it look like a phone call from joseph mcstaywe have the evidence to prove that, yes. >> reporter: how strong is that proof? how reliable is the evidence gathered at the mcstay house weeks after investigators say they were murdered there? >> tons of critical evidence could have been lost in those first 15 days. >> reporter: 15 days in which people were in and out of the the house. >> so many things in there that could have been relevant to the case. >> reporter: investigative journalist steph watts. >> we don't know if somebody in that house was related to or had knowledge of the crime could have removed items that could have been significant to solving this case. could have removed items that could have indicted them in this case. >> i don't think that you can seal a home for that long unless you are actually investigating a murder, and at that time, it wasn't. >> we know that the family members went in and out and susan mcstay cleaned the counters and she couldn't stand that it was dirty and cleaned the diapers, and mike mcstay

joseph mcstay's mother went in. she cleaned the counters.e case and chase merritt said he was at the house. what did he do if they were killed at the house? did he spend days cleaning it up. >> mr. merritt is representing himself. >> at first it wasn't like that. recently he decided he wanted to represent himself. he believes he has six to eight months to live at the most. he wants to get out of jail and he doesn't think he has a lot of time left so he decided to take it on himself. >> thank you for being with me. you can catch randi's entire documentary "chasing a killer inside the mcstay family murders" tonight at 9:00 eastern on cnn. the next hour of "cnn newsroom" after a break. just about anywhere you use sugar, you can use splenda®... ...no calorie sweetener. splenda® lets you experience... ...the joy of sugar... ...without all the calories. think sugar, say splenda® you just got a big bump in miles. so this is a great opportunity for an upgrade. sound good? great. because you're not you you're a whole airline... and it's not a ticket

. >> detectives are taking a close look at joseph mcstay's business relationships. >> he spoke to usrview. >> i was the last person who saw him so of course i was a person of interest. >> did detectives ask you if you killed joseph mcstay and his family? >> i don't recall them asking me that. >> nothing that direct. >> no. i don't recall them being that direct. >> you took a polygraph test. what did it show? >> i don't know. >> you passed the polygraph. >> apparently. i mean, i haven't -- i kind of simply assumed, well apparently that resolved any issues that they may be looking at with me. >> randi kaye is here with a preview. just watching him sitting across from you cool calm collected. >> yeah. >> little did he know what he had in store. >> the d.a. is so sure they have the right guy. first of all, some of the evidence, chase merritt, in our exclusive interview, told us he was definitely the last person to see joseph mcstay. you have to wonder about that. he also lived at the time the family disappeared about 20 miles from where their remains were found four years later in the mo

he was working for joseph mcstay's waterfall business. he made these custom waterfalls. from family members that joey mcstay wasn't very happy with the work that chase merritt was doing. it was getting shoddy. he was having to replace waterfalls and give money back. it was really costing the business a lot of money. there was also a big deal worth something like $9 million that the two of them were coming into. if joey mcstay was looking to cut chase merritt out of that deal investigators say that was a motive to get rid of the mcstay family. >> fascinating. thank you so much. be sure to tune into randy kaye's documentary that takes you inside the latest on this case. "chasing a killer inside the mcstay family murders" airs tonight at 9:00 p.m. eastern on cnn. salesman alan ames books his room at laquinta.com, he gets a ready for you alert the second his room is ready. so he knows exactly when he can check in and power up before his big meeting. and when alan gets all powered up, ya know what happens? i think the numbers speak for themselves. i'm sold! he's a selling mach

chase merit had lunch with joseph mcstay at a chick-fil-a in california. happy and they were celebrating big business coming in. in other cases he spoke with patrick mcstay, the grandfather in this case and he had told patrick that joey and he had had a fight and that joey wasn't happy with some of the work he was doing. we're not sure which case is fact. >> well now there's an even i guess more bizarre twist. i understand that a judge has granted him permission to represent himself? i was shocked by this. >> reporter: and so was the judge actually. the judge tried to talk him out of it. he told him several times that this is unadvisable. he kept saying i want to do it. i want to to it. the reason he wants to do it is he says he's not a healthy man. his lawyer has said that he has congestive heart failure. he seems to think he has six or eight months or so to live so he wants to move this trial along. now he's going to represent himself. he could end up very well cross examining and questioning people who he says we should be looking closer at. certainly t

. >> did detectives ask you did you kill joseph mcstay and his family?nothing that direct. >> hmm? >> not that directly. you passed the polygraph. >> i kind of assumed that resolved any issues that may be looking at with me. >> randy is joining us now with more. in this interview, was there really any sense he could have been involved. he was his best friend right? >> he was. he was polite and soft spoken. he was the last person to see him. he also lived about 20 miles away from where the family's remains were found about four years later. there were 100 pieces of evidence, including dna that was taken from those shallow graves found in the desert. he was also the first person at the house. we know he was there. we know the d.a. believes the family was killed with blunt force trauma and there would have been blood splatter. the sheriff's department didn't get into there until two weeks after the family disappeared. the d.a. is looking to see if someone got in the house and cleaned it up. >> what's next? >> he goes back to court april 7th for another prel

chase merit is charged with murder in the deaths of joseph mcstay and his wife summer and their two boys remains were found in the california desert nearly four years after they disappeared. a short time ago, merit was in court for a hearing and he is representing himself. the mcstays went admitsing in february 2010 and for years, no one knew what happened to them. when i talked to chase merit, a family friend, before he was named as a suspect. he says detectives questioned him and this is what he says they asked him. >> the standard questions, you know, just do i know anything about them disappearing. did i have anything to do with it, just -- just the standard questions. probably they asked everybody. >> as far as you know you were one of the last people to see him, right? >> yeah. when he left the ranch, nobody else -- although i think somebody -- there's another person or two that he talked to. i'm not sure. >> but you were the last person he saw. >> i'm definitely the last person he saw. >> now i spoke to chase merit a year ago january in his only television interview. there you hav