A change of judge is governed by Rule 42(f) of the Rules of Civil Procedure. If the judge has not yet ruled on any contested issue, AND the request meets certain timing requirements, you are entitled to a change of judge. All you have to do is file a Notice of Change of Judge by following the steps in Rule 42(f). I've attached a link to a list of the Rules of Procedure, so you can read the rule yourself. Pay careful attention to the timing requirements.
If the judge has already issued a ruling on a contested issue, your only recourse is to file a motion to have the judge removed for cause. There are only five allowable reasons to remove a judge for cause, and It is incredibly rare for these types of motions to be granted. If you want to learn more about removal for cause, check A.R.S. 12-409.
I would not put too much weight in what upset parents say about judges. No one ever posts that their Judge was "fair" or "nice", as that is what is expected. As such, the web tends to attract negative comments. I would imagine that most of the negative postings are from unrepresented individuals who do not fully understand why the court made certain rulings.
In any event, Noticing a judge for 'cause' based on some bad internet postings is not a good idea. If you are still early enough to get a different judge pursuant to the rules, you can certainly do that, but you may not like that judge any better if you are just relying on web postings.
One last thought...judges rotate in Maricopa County. Here is the link to the anticipated rotations this summer. It is possible that you will be getting a new judge anyway.
This general information does not create an attorney client relationship between the questioner and the author. The internet is NOT a place to get 'legal advice'...although gathering general information is always helpful.
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