Ariz. Const. art. IX, § 14

No moneys derived from fees, excises, or license taxes relating to registration, operation, or use of vehicles on the public highways or streets or to fuels or any other energy source used for the propulsion of vehicles on the public highways or streets, shall be expended for other than highway and street purposes including the cost of administering the state highway system and the laws creating such fees, excises, or license taxes, statutory refunds and adjustments provided by law, payment of principal and interest on highway and street bonds and obligations, expenses of state enforcement of traffic laws and state administration of traffic safety programs, payment of costs of publication and distribution of Arizona highways magazine, state costs of construction, reconstruction, maintenance or repair of public highways, streets or bridges, costs of rights of way acquisitions and expenses related thereto, roadside development, and for distribution to counties, incorporated cities and towns to be used by them solely for highway and street purposes including costs of rights of way acquisitions and expenses related thereto, construction, reconstruction, maintenance, repair, roadside development, of county, city and town roads, streets, and bridges and payment of principal and interest on highway and street bonds. As long as the total highway user revenues derived equals or exceeds the total derived in the fiscal year ending June 30, 1970, the state and any county shall not receive from such revenues for the use of each and for distribution to cities and towns, fewer dollars than were received and distributed in such fiscal year. This section shall not apply to moneys derived from the automobile license tax imposed under section 11 of article IX of the Constitution of Arizona. All moneys collected in accordance with this section shall be distributed as provided by law.