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I defer to my colleague on matters of AZ law. In addition to what he said you should be aware that there are some scam operations emanating from AZ which send collection letters that look like they come from a court. The way to be sure is to look for the return address on the envelope and the identity of the Court on the ticket as well as a telephone number for the clerk's office. If all these items are not there, don't pay; you are being scammed.
For extensive information on the subject see www.highwayrobbery.net.