New theory?

[gumshoe1]

The evidence is that John's fibers link him to sexual assault and Patsy's fibers link her to strangulation. How does BDI explain this?

John molested JonBenet. Burke inflicted the fatal head blow on JonBenet. Patsy garroted a braindead JonBenet to make it look like an intruder killed JonBenet.

 

[Swirlz]

John molested JonBenet. Burke inflicted the fatal head blow on JonBenet. Patsy garroted a braindead JonBenet to make it look like an intruder killed JonBenet.

I don't believe the series of attacks was a group activity with all 3 surviving family members participating or that there is any evidence to suggest this.

 

[gumshoe1]

I don't believe the series of attacks was a group activity with all 3 surviving family members participating or that there is any evidence to suggest this.

I don't think that the series of attacks was a group activity with all three surviving family members participating either. John (individually, not as a group activity involving Burke or Patsy) molested JonBenet in the few weeks preceding Christmas 1996. Burke (individually) inflicted the fatal head blow from sometime between 11 pm on Christmas night to around 01:00 a.m. on December 26. Patsy and John did not want Burke to inflict the fatal head wound on JonBenet. Burke just accidentally killed JonBenet on his own. So the killing was not really a group activity.

Then Patsy garroted JonBenet to make it look like an intruder killed JonBenet. John and Patsy staged the sexual assault of JonBenet to account for the evidence that someone was molesting JonBenet (which would be found during autopsy).

Edited to add: Actually, I believe PDI. But I just listed this BDI scenario to answer Swirlz's question.

Although I think PDI is more likely, I do think that it is quite possible that the BDI scenario I mentioned is what happened.