The justices ruled 8-1 to affirm a previous decision by King County Superior Court, which sided with the city against opponents, including the National Rifle Association.
The city has been imposing the tax of $25 per firearm and 2 or 5 cents per round of ammunition for more than a year and a half, following City Council passage in 2015.
During that time, the lawsuit brought by the tax’s opponents has been moving through the courts.
The plaintiffs have said the tax violates a Washington lawthat bans cities from regulating firearms, reserving that authority for the state. Seattle claims the tax is legal because taxation is different from regulation.
The majority opinion concluded in part that the city’s ordinance does impose a tax, rather than a regulation, on firearms “because its primary purpose is to raise revenue for the public benefit.”
The city won the first battle in December 2015, when a King County Superior Court judge came down on the side of the tax, ruling it could take effect.
Opponents then took the case to a state appeals court, which passed it on to the state Supreme Court.
“Under Washington law, a charge intended to raise revenue for the public benefit is a tax,” Justice Debra L. Stephens wrote in Thursday’s majority opinion.
“While courts should be dubious of regulations masquerading as taxes (and vice versa),” the opponents of Seattle’s tax offered “no convincing evidence that the ordinance has a regulatory purpose or intent,” Stephens added.
In addition to the NRA, the plaintiffs include the Bellevue-based Second Amendment Foundation, the National Shooting Sports Foundation and two local gun owners.
Outdoor Emporium, a store in Sodo that sells guns, and Precise Shooter, a gun store that abandoned its Green Lake location after the tax was adopted, also have been part of the suit.
They’ve said the point of the tax is to drive gun sellers out of the city, while proponents, such as City Councilmember Tim Burgess, have said the intent is to raise money for gun-violence research as part of an effort to stop it.
When Burgess proposed the tax, he said the city’s budget office had estimated it would raise $300,000 to $500,000 annually. It raised less than $200,000 during its first year.
Seattle has been waiting to spend that money until the lawsuit is resolved.
In a statement, the Second Amendment Foundation said Thursday’s ruling shows how much elections for state Supreme Court justices matter.
“The high court’s decision to uphold what clearly appears to us as a violation” of Washington’s law barring cities from regulating firearms “is proof positive that the court places political correctness above the rule of law,” executive Vice President Alan M. Gottlieb said. “Gun owners must get more involved in Supreme Court races.”
Gottlieb called the ruling “a loss for the rule of law, firearms dealers and gun owners living in Seattle” and also “a slap in the face to the Washington Legislature.”
Other plaintiffs, including the NRA, didn’t immediately comment Thursday.
Burgess called the ruling a “huge win” and said he hopes other Washington cities “now feel comfortable to follow suit” by adopting their own taxes on gun sales.
“I’m thrilled to see our Supreme Court so strongly uphold Seattle’s gun-violence tax,” he said in a statement Thursday. “We knew from the start that we had a strong and sound legal case, and I’m proud that the tax proceeds can continue funding gun safety research and prevention programs at Harborview Medical Center.”
The councilmember added, “Gun violence costs the city and county $180 million per year, and I believe the gun industry should help offset some of those costs.”
The Alliance for Gun Responsibility joined Burgess in hailing the new decision.
“The gun lobby has tried — and failed … to use the courts to block this commonsense policy that will fund these critical investments,” the Alliance said in a statement.
“Today’s ruling is a clear message that their campaign to deny the public factual information about gun violence is not welcome in Washington state.”