This pertains to dog owners picking up their dog waste.
As long as dogs have been a part of urban life, cities have issued attempts to control them with anti-excrement campaigns going back to the 1920s. In the 20th century, there were public concerns having to do with horse-drawn vehicles and the mess that horses left. With efforts to clean that up, the mess left by dogs became more evident. New York was the first to introduce its “pooper-scooper” law in 1978.
In answer to your question, most cities have their own ordinances (and fines) when it comes to dog fecal matter. Usually, signs are posted to warn pet owners of that. For Maricopa County and unincorporated areas, there doesn’t seem to be one — yet.
However, in the Sun City Home Owners Association covenants, conditions and restrictions, Section 8-Animal Restrictions does state that “Owners agree to clean up after the pet when the pet is outside of a residential unit; and otherwise maintain the pet so at no time does the pet create a health hazard.”