Some excerpts from Williams' article -
Reasonable people can differ on whether the photo radar statute is constitutional. However, what is not debatable is the very clear sanction language of A.R.S. § 41-1722(B). The fine for a violation of this statute is $181.50. It does not matter whether the defendant was going eleven miles per hour over the speed limit or one-hundred. The fine for other perhaps more creative photo radar charges (e.g. driving while suspended, expired registration) is also $181.50. The statute does not authorize anything else and trumps everything else.
Please keep in mind that neither the courts nor Maricopa County get that money. The photo radar statutes require justice courts to be an involuntary collection agent for the State of Arizona and for the so-called Clean Elections Fund, which gives money to the political campaigns of politicians running for legislative and for statewide offices.