I think this was a random killing, in that it wasn't specifically for Heidi and David. I believe the murderer was there waiting and whoever had come to the scene would have been murdered. It's my thought that it most likely was a sexual assault. I think the murderer approached the vehicle from the driver's side and they tried to run from the passenger side when they saw him. After David was shot, I think the killer chased Heidi and attacked her, assaulted her and then killed her. She may have even stopped when she heard him shoot David out of fear for David. Putting myself in that position, I think I would have stopped at a gunshot out of fear that my friend had probably been shot. I don't think you would be thinking clearly at a moment like that. I don't believe the killing happened because of a robbery. I like LucyOso think that was an after thought. This is all JMO and have no info to back it up. I do think a lot of info has been withheld from the public, but I'm not sure why. I also believe the killer was local to the area at the time. Like MrT said above, he may have lived or camped there. When this happened he may have moved on. I had never heard before that a sweat shirt was found at the scene. Wonder if it belonged to Heidi or David, or the killer? I had heard about the hairs and also DNA in the form of fingerprints.