Ariz. Rev. Stat. § 28-873
A. Except if necessary to avoid conflict with other traffic or if in compliance with law or the directions of a police officer or traffic control device, a person shall not stop, stand or park a vehicle in any of the following places:
3. In front of a public or private driveway, except that this paragraph does not apply to a vehicle or the driver of a vehicle engaged in the official delivery of the United States mail if both of the following apply:
16. On a controlled access highway except:
B. A local authority may allow motor vehicles providing a public entity's public transportation service to stop on a state highway or state route for the purpose of allowing passengers to enter or exit if all of the following apply:
C. For the purposes of this section, "public transportation vehicle" means any vehicle that either: