With all respect, in my opinion it is premature at this point to CONCLUDE that Burke did anything. One might have some questions, or wonder, but that's all that is reasonable at this point.
The facts are these: There is NO physical evidence tying Burke to any crime at all. This cannot be said for mom and dad. Further, there is circumstantial evidence to suggest that Burke did not do it -- specifically, the parents sending him out of the house, and out of there control, that morning. Unless they were convinced that Burke was anb emotionless monster and psychopath, they would never confidently unleash a nine-year-old and trust that he wouldn't confess and bury them all. No parent would easily believe that about their own son, and if they DID believe that they couldn't trust him not to blurt the truth (or some malicious fiction) just to watch the world burn.
And that, my friends, is the glaring chasm in the BDI theory.
When they turned him loose that morning, they did so knowing that he had no actual facts to disclose. More, they likely expected to be arrested, and they wanted him out of the home when that happened.
This release tells us nothing, other than that the Grand Jury did not have a clear picture of which one of the two parents actually murdered the girl.
IN MY OPINION.
Remind me.....who did the Ramsey's send Burke away with that day? I cannot remember.
I think, obviously, PR and JR had to be pretty confident that BR would not say anything to send him away. And he hasn't. Heck, he hasn't even come forward as an adult to discuss how he wants to find the murderer of his sister.