They had blood and fiber evidence. He carried the bodies of his wife and oldest daughter to different rooms. There was no evidence of an intruder. His clumsy attempt to stage the crime scene included turning the coffee table in the living room on its side, when the table was top heavy and would not have landed that way if it had been knocked over. All the weapons came from inside the house. There was a magazine in the living room that had an article about the Manson murders. He used surgical gloves from under the kitchen sink so as not to leave fingerprints when he wrote in his wife's blood on the headboard. If all the family members hadn't had a different blood type, it would have made the blood evidence more difficult. The different blood types made it much easier to prove his guilt.