kevin was a suspect that we needed to find out the validity of his statements, whether he had gunshot residue on his hands, whether he was even able to shoot a gun, given his physical disabilities. reporter: but a suspect? they checked his hands for gun powder residue. negative. you have to look at everybody, unfortunately. sometimes hurt feelings, but you have to get down to the facts, too. reporter: but facts can be tricky things. and in this case far more elusive than anyone might have imagined. many some clies were elusive, but some were right out in the front, like the two that dramatically narrowed down the circle of suspects. coming up. those are huge. it eliminates everybody down to only those people that have access to those two keys. when dateline continues. o when dateline continues
you must immediately wonder who. right. well, you wonder if it s a completely random act, some stranger and it was a mistake or an accident, or you develop a list of people that might have a reason to have shot him. reporter: to police, it didn t look random. nothing was taken. the killer struck with precision accuracy and got clean away. but there was something that intrigued detective voth that night. it was a clue they found in bill mclaughlin s closet. we do a search of the house with the permission of kevin. we re told there are weapons in the closet upstairs. when you come across that many weapons, it becomes surprising. reporter: bill was an avid gun collector. he kept dozens in his newport beach house. not just antiques, revolvers, including seven modified m-16 assault rifles. dangerous stuff in the wrong hands. we didn t know if somebody maybe was upset with the sale of a gun or something.
anybody involved has a possibility of being the murderer. reporter: so voth questioned nanette and bill s own grown kids, couldn t eliminate anybody yet. we looked at the girlfriend and also looked at the daughters because anyone who stands to gain money in this situation is a potential suspect. reporter: bill s ex-wife was way off in hawaii. they d been divorced for years. still the detectives talked to her. then there was kevin, bill s disabled son, and the only other person in the house at the time of the murder. newport beach emergency. reporter: it was shortly after 9:00 p.m. when kevin heard the gunfire. he was upstairs, still debilitated by those car accident injuries. he labored to make his way to the kitchen where he found his father. [ inaudible ] i can t understand what you re saying. reporter: too disabled to explain he needed help.
beach police. when a thing like this happens, i mean, it s really an execution-style killing. this was obviously someone who intended to kill your dad. you must immediately wonder who. right. well, you wonder if it s a completely random act, some stranger and it was a mistake or an accident, or you develop a list of people that might have a reason to have shot him. reporter: to police, it didn t look random. nothing was taken. the killer struck with precision accuracy and got clean away. but there was something that intrigued detective voth that night. it was a clue they found in bill mclaughlin s closet. we do a search of the house with the permission of kevin. we re told there are weapons in the closet upstairs. when you come across that many weapons, it becomes surprising. reporter: bill was an avid gun collector. he kept dozens in his newport beach house. not just antiques, revolvers, including seven modified m-16
he encouraged us to do things in the community, the three of us kids would go to nursing homes and put on a talent show for the elderly. how unusual. you have to understand where my dad came from, a very low-income family, as we d call it today. so he always appreciated what he had, and he worked very hard for it. reporter: bill s children worked hard, too, supported libraries in the third world, orphanages in africa, gave wheelchairs to the poor in latin america. rewarding work. but, as time passed, they began to think the fairy tale had it all wrong. seemed to them like it was the evil stepmother who got to live happily ever after. certainly not them. five years after the murder, in 1999, the sisters lost their brother kevin in a drowning accident. he never did recover from the damage the drunk driver did or the trauma of finding his murdered father. so both men of the family were gone. and hope for justice faded away.