Portlanders must continue to pay a controversial tax that funds arts education in schools after the Oregon Supreme Court ruled unanimously Thursday that the tax is legal.

Retired Attorney George Wittemyer sued Portland in March 2013, asserting that the tax violated the Oregon Constitution's prohibition on a flat-rate per-person "head tax."

The district and appeals courts that heard his case upheld the tax's legality. Wittemyer appealed those rulings, and the high court also rejected his challenge.

Portland voters in 2012 imposed the arts tax of $35 per person to help expand arts and music education in schools.

The tax does not constitute a head tax because it exempts some taxpayers based on income and household resources, the court ruled.

Individuals and households at or below the federal poverty line are exempt from the tax, as are taxpayers earning less than $1,000 per year who live in non-poverty households and wage-earners under age 18. The arts tax also does not apply to income from Social Security or Oregon public employee pensions.

Justice Jack Landau wrote the opinion, which was agreed to by all six justices who deliberated on the case. Landau announced this week that he will retire later this year.

"Poll or head taxes are ancient in origin," Landau wrote. He traced his decision back to biblical times, through Roman Egypt and England in the Middle Ages to reach a conclusion that the prohibition does not apply to today's art tax that funds children's dance classes.

Wittemyer said he supported funding arts for children — like his trumpet-playing grandson —but filed suit because he could not condone an unconstitutional tax of any kind.

City officials pointed out the tax exempts many people, including children, low-income individuals and households and retired public employees.

Deputy City Attorney Denis Vannier argued those exemptions make the tax legal. The Portland Public School District and the League of Oregon Cities, which represents 241 incorporated cities, filed briefs supporting the city.

"Today's decision is a big win for Portland's kids," Portland Commissioner Nick Fish said in a statement. He is the Portland City Council's liaison to the Regional Arts & Culture Council that staffs the tax's oversight committee.

"Thanks to the ruling of the Oregon Supreme Court, over 30,000 Portland children will continue to have arts education in school," Fish said.

Jeff Hawthorne, interim director of the Regional Arts & Culture Council, said in a statement that continuing the tax will enable every grade school in Portland to have at least one art, music or dance teacher on staff and further investment in nonprofit arts organizations.

"We are grateful to the Oregon Supreme Court for affirming the legality of the arts tax once and for all," Hawthorne said.

The city has struggled to collect the arts tax since its implementation. It has only collected an average 74 percent of the tax each year, according to a report presented to the city council last week.

City officials have also overspent on collections, the report found. They exceeded a voter-mandated 5 percent cap on administrative expenses, diverting almost $1 million more from arts grants than they should have from 2012 to 2015, the report said.

Portland Mayor Ted Wheeler does not yet have a position on how to address the excessive administrative spending, his spokesman Michael Cox said in a text.

"He continues to work with his council colleagues on the issue," Cox said.

--Jessica Floum

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