I have considered only the evidence too, but have came to the opposite conclusion. Fibers from John's shirt were found in JB's genital area, and fibers from Patsy's Christmas party jacket were found in the paint tray and on the sticky side of the duct tape which covered JB's mouth. This is very incriminating evidence.I don't think neither[sic] parent is guilty, and I have considered only the evidence.
Then there's the idiotic ransom note, and the body left in the home, with ligatures which didn't bind, a bogus garrote, and duct tape placed on the dead child's mouth.
The parents' strange behavior stands out too. Behavior is also circumstantial evidence. Their total non-cooperation with the police right from the beginning just screams that these people had something to hide.
And five days after the murder, they said on TV that the were not angry at the killer and wanted to get on with their life. Enough said.