Most children don't have a prior track record of lies in legal cases.
This case was just too dirty to sort through. Since the mother was there and an active player in the relationship and proximity of the child to MJ... She's relevant. And if she'd shown to make things up and get her kid to play along, the case has to be thrown out.
This whole trial is a circus side show.
We'll have to disagree on that. Child molesters typically choose that kind of child deliberately, sort of like insurance if they get caught. Jackson did so, too, in my estimation. If the truth were known, I'm betting that he investigated this family first, before he started messing with the boy, just to make sure they wouldn't be believed. He chose well, apparently. (But not for the boy...)