drinking 16-year-old caleb gordley mistakenly entered the wrong house and was shot dead by his neighbor just two doors down. In the immediate aftermath of the shooting, caleb's father, shawn, was on a... See More
drinking 16-year-old caleb gordley mistakenly entered the wrong house and was shot dead by his neighbor just two doors down. In the immediate aftermath of the shooting, caleb's father, shawn, was on a mission. And that was to let the world know my son made a mistake. He was not there to harm anybody. He was not there to rob anybody. That's all I cared about. Letting everybody know he went to the wrong house. Reporter: You said right after this happened that you felt forgiving towards your neighbor? Correct. Reporter: Do you still? No, not 1% forgiving. I'll tell him right here and right now. I apologize for my son entering your house. I will take that. Beyond that, there is no forgiveness. Once I got the details, I was outraged. This is a horrible, horrible set of circumstances for the family, horrible set of circumstances for the shooter. Reporter: But five months after donald west wilder, seen here, and identified to us by neighbors, shot and killed their teen son. My son is gone. Reporter: Shawn and jennea are no longer conciliatory. It sounded like a mistaken identity. Someone thinks there's a burglar in their home and they're trying to defend themselves. At no point, during the homeowner's account of the events, did he ever describe caleb in any way as being aggressive, ill intent. He did not approach him. He did not come after him in a violent way. Reporter: In fact, kory carico says his friend caleb was visibly impaired when he tried getting him home. He was stumbling a lot. He fell down on the sidewalk a couple times. I probably should have kept him at my house or waited a little bit longer. Reporter: Shawn is convinced that his son was confused, since his home has a nearly identical floor plan to the neighbors. From the vantage point of wilder upstairs, shawn showed us what he thinks happened according to the police report. He was crawling into his window? Correct. Reporter: Where do you think the homeowners saw him first? According to the police report, the homeowner came down this hall, immediately saw caleb in the kitchen area, he saw his face. He did not recognize him, and he yelled at him to get out of the house. Reporter: He suspects his intoxicated son believed he was hearing his dad's angry voice. Caleb would have continued on thinking he's going to his bedroom, you think? Yes. Correct. Reporter: But remember, the 6' tall boy is in wilder's home and headed toward the bedrooms of wilder's fiance and her son. The homeowner said he made eye contact with caleb and there was a dazed look on his face. So, he knew he was on drugs, alcohol, whatever the case may be, and as he came up the steps, he said he saw no weapon. Reporter: Wilder then yells out and fires a warning shot, fearing the unknown intruder who's making his way upstairs near his family. Caleb, then, according to a statement, turned around, didn't attack the person shooting at him and simply said, according to the statement, "you just shot me." Reporter: Then the end for caleb, an ending shawn finds unconscionable. The autopsy report revealing the cold hard fact that caleb was shot in the back. Thewnomeoer angled against the wall and fired, through his chest, and then fourth shot at his head, then he aimed at his head, missed, and then caleb took two more steps and fell face down on the floor, right in front of what he thought was his own bedroom. I don't care if you're in the wild west. I don't care if you're in the hood. There is no honor in shooting somebody in the back. Reporter: So why would the homeowner fire multiple times when this person didn't appear to have a weapon? It's 2:30 in the morning. You have a person that actually comes in through a window. The alarm sounds off. He was 6' tall, unknownst to the homeowner, wearing dark clothing. The homeowner advised him to stop, you know, and that he would shoot, and caleb continued to come forward. He lined himself up at the perfect angle to shoot a hollow-point bullet through my son's lung and explode his chest and then a fourth shot at his head for good measure. That's what he did. Reporter: Do you see it as murder or accidental shooting? Murder. Reporter: Murder? Yes. He shot him in the back. If you're really in fear of danger of your life and your family's life, why would you allow a person that you -- that appeared to be dazed to you, walk right past you and then you shoot him in the back? If caleb would have crossed that street right there and get hit by a car, I would have nobody to blame but caleb. I have somebody else to blame for my son's death. I just do. Reporter: This kid is a kid of color, black kid. Did that have any impact on this case? I can't see that it would. The entire situation was just bad all the way around. Somebody coming into your house. Somebody, you know, not stopping when you're giving them commands to stop. Somebody continue to advance on you. Somebody going up the stairs where your family is. Reporter: The homeowner has not spoken out publicly, have you had any sense of how this has impacted him? In the conversations with my detectives, I understand that he was devastating -- devastated by what had happened. So much so that he had to take a couple weeks off. Reporter: After an investigation, no charges were filed against donald west wilder, a volunteer firefighter who owns a consulting company. Though his attorney he declined our request for an interview, saying, "the incident was an fortunate tragedy on every level. But as we are not confident that participating in your program would contribute to the healing process. We are unwilling to so participate." Ten months after their son's death, shawn and jennea gordley, still can't understand how a teenage mistake can end so tragically. The man who took her son's life did reach out to the gordleys, through his attorney, saying he was sad about what happened, but shawn threw out the note, offended by its formal tone. Do I hate him? No. Do I want him put away? No. I don't think that's going to solve anything. Reporter: Do you want to hear from him personally? I would love to. Reporter: He's two doors down? Two doors down. Reporter: Do you still see this neighbor? I never saw him before. I haven't seen him since. Reporter: Some people would have packed up and moved right away, but yet you've somehow managed to stay here. The first few months, there was no way I was leaving. I keep the door closed because it smells like him in here still, after all these months. I can smell him right now. I can smell him, on his blanket, on his pillow. We haven't washed anything. We haven't vacuumed. I come in here, sometimes, I'd -- I'll take a nap on his bed. Reporter: And he awakens to a wall of emotional memories, scrawled by caleb's classmates who were shattered by their friends sudden death. I don't know anyone who didn't like him for any reason. He just put a smile on your face. Absolutely great kid. This was his 16th birthday. So this is his last birthday. Reporter: His son would be 17 now, a high school senior making college plans with his friend kory. He's such a good friend. It's a shame you never knew him. He was such a funny person. I truly believe that my son was a gift. We had 16 and half awesome years. I will hold onto that. A sad and complicated case for sure. Was that homeowner justified in taking action that night or do those parents deserve an apology in person?
This transcript has been automatically generated and may not be 100% accurate.