Bridget Dowd/KJZZ

The Arizona Cardinals play at State Farm Stadium in Glendale.

On its first day back in session, the U.S. Supreme Court upheld an Arizona high court ruling protecting a multimillion-dollar tax source used to fund sports and tourism.

At issue was whether Pima and Maricopa counties can use revenue from a car rental tax to fund the state Sports and Tourism Authority or whether that money should be constitutionally protected and held exclusively for statewide road projects.

The most recent audit for Maricopa County shows the 3.5% tax contributing nearly $52 million to the authority's annual budget, with nearly $14 million paying off the bonds to build the Arizona Cardinals stadium.

However, the Arizona Constitution requires that taxes collected for car registration or operation go strictly to the public roads fund.

By refusing to hear the case, the Supreme Court backed Arizona's high court decision that nothing is wrong with using the car rental tax, which is paid largely by tourists, to pay for tourism programs.