One qualification not apparently required of judges...

....is apparently to be mature enough to handle criticism, at least in California. How so?

The HSLDA report on how they got a California anti-homeschooling ruling overturned specifically notes that one of the critical things they did was to phrase the appeal in such a way to not offend the judges. A quote:

“We had to thread a needle, because we had to bring to the court’s attention these gross oversights that we knew weren’t necessarily the court’s fault because they hadn’t been presented to the judges in the earlier briefing,” Mason said. “We had to say, ‘Hey, you made a mistake,’ without offending the judges so much they dismissed it entirely.”

Now while I understand the necessity of being polite, but take a close look there. More or less, the speaker is saying that demonstrating a gross oversight in the law to a California judge is likely to get him to dismiss one's appeal without even considering its merit.

In some courts, that would mean that the greater the error by the court, the less its chance of being fixed. Sad to say, it explains some things I've seen. Is it too much to ask that judges also be mature enough to handle criticism?