John Ramsey himself said that very morning that it was an 'inside' job.
The detective on scene reached for her gun when she looked in Johns eyes as he laid his dead daughter on the floor...she knew.
My first thought was the brother. Sibling jealousy and rage. That would have made the parents cover up for him and make them look guilty themselves. I know he was only 9 but it could happen. The one thing I am sure of is that it wasn't Patsy.
It is my opinion that Ramsey is/was a Mason and had connections with the local Masonic lodge in Boulder. The Cheif of Police is probably also a Mason. They are both probably high up in the club.
One did not want to rat out the other and this is why neither Ramsey nor his wife were ever charged