Opponents of Portland's much-maligned arts tax have called it flawed, regressive or just plain unfair.

One thing they can't call it: illegal.

On Wednesday, the Oregon Court of Appeals upheld an earlier ruling and reiterated that the arts tax isn't prohibited by the Oregon Constitution.

Portland resident George Wittermyer argued that the arts tax is a "poll or head tax" that applies to everyone. If true, it would be illegal.

But the Court of Appeals said that's not what Portland's arts tax actually is.

First, judges had to settle on a modern definition of a head tax, the origins of which date back more than 100 years as a mechanism to pay for roads in Oregon.

They decided such a tax was "a single, fixed amount imposed per capita, sometimes subject to limited exclusions, without reference to an individual's income or property."

Portland's arts tax is $35 per person for anyone 18 or older who earns income. But it offers exemptions based on poverty, the amount of income (less than $1,000) or the type of income, such as government pensions.

That means it's not assessed per capita, according to the Court of Appeals, and therefore it's legal.

"We are pleased the Court of Appeals agreed with the City of Portland that the Arts Tax is constitutional," Thomas Lannom, director of the city's revenue division, said in a statement.

Next week, the City Council will consider using a collection agency to recoup unpaid taxes. That could represent a big shift for the city, as some commissioners have openly said they don't want to ruin residents' credit histories trying to collect $35 in unpaid taxes.

City officials originally projected that 85 percent of residents who are required to pay the arts tax would pay. Instead, rates have been significantly less: 72 percent for 2012, 70 percent for 2013 and 68 percent for 2014, as of March.

The city reported gross taxes of $9.3 million for the 2014 tax year.

Money from the tax helps pay for teachers and non-profit arts programs.

-- Brad Schmidt

503-294-7628

@cityhallwatch