But the jury has to be told about that in the context of the testimony. They only get what the prosecutor presents to them.
If, as is stated elsewhere on this thread, the prosecutor FAILED to provide an expert in the area of child abuse, "grooming", and child abuse accommodation syndrome, he is a total incompetent.
When you add prosecutorial incompetence to the amount of dirt and sleaziness proved WRT to the mother in this case, you have a sure loser on your hands. The prosecutor had to KNOW he had a credibility problem with this parent and this child, the best way to counteract that would have been with an authoritative, credentialed expert who could lay out the story line for the jury. (A good prosecutor doesn't just showboat and hold press conferences - he gives the jury a story line to follow throughout the evidence.)
I can't believe he didn't do this. He must be the worst DA in California.
The judge may not have allowed testimony about child molesting patterns, now that I think of it. I do recall that he wouldn't allow certain testimony about spousal abuse (the boy's father was abusive). This judge made several decisions I found odd.