Anything more than supposition and coincidence would be a good start.
Be more specific. Be mindful that objects with fingerprints can be moved from place to place, and that fingerprints can be scanned and duplicated. Video and phototographs can be manipulated to no end, of course. And eyewitnesses can easily be mistaken about many things. I find it hard to imagine a case where one couldn't formulate a scenario consistent with an accused killer's innocence. But the issue of plausibility rears its ugly head.
Scott Peterson is alleged to have done many things that would suggest he knew his wife was dead before her body was discovered. Collectively, they constitute pretty strong evidence that he knew his wife was dead. That Scott Peterson had such knowledge is not mere supposition; it is a theory which the prosecution has supported with considerable evidence.
You might argue that even proving that Scott Peterson knew of his wife's death would not prove his participation in her murder. That would be correct. On the other hand, possession of guilty knowledge does create a strong presumption of guilty involvement, just as possession of stolen property creates a strong presumption of involvement in theft. If the police find in a person's garage a large amount of merchandise that has been stolen from the area, that would generally be adequate to prosecute the person for theft even if nobody actually saw the person steal any of it. It may be in some cases that a person might have a reasonable explanation for possessing the merchandise; if, for example, he could produce a receipt that showed he paid a reasonable amount of money for it at what he reasonably believed to be an estate lot sale, that could be grounds for acquittal. It is not, however, the job of the jury to speculate that he might have acquired the property by what he thought were legitimate means. If the defense wishes to claim that he did so, the defense must claim that.
So again, I ask you to please break down for me: do you believe that the state failed to provide adequate evidence to show that Scott Peterson knew of his wife's death, or do you believe that such knowledge does not constitute evidence of his involvement in her murder?