A gun control law Multnomah County passed last year goes on trial Wednesday. Residents in Gresham and Troutdale are challenging the law.
Their case isn't really about gun rights. It's a legal turf battle between the county and cities.
Multnomah County passed its gun ordinance last spring.
Deborah Kafoury, a county commissioner at the time, said then the shootings at Clackamas Town Center and Sandy Hook Elementary school moved her to push for tighter gun control at the local level.
"I'm very proud of what we're doing today," Kafoury said at the time. "I think it's small and incremental steps that are going to save people's lives."
The county law bans the open carry of most loaded guns in Multnomah County. Concealed carry and guns for hunting are still allowed with the right permits from the state. And the ordinance creates a new offense: endangering a child by allowing access to a firearm if it isn't safely locked up.
In Portland, the county ordinance didn't attract much notice, in part because the city already has similar regulations on the books.
But the reaction in Gresham and Troutdale was a different story, says attorney Bruce McCain.
"There's so much confusion right now in east Multnomah County, between mayors and city councils and police chiefs and the sheriff," McCain says. "Nobody knows whether this thing's enforceable inside their cities or not."
McCain represents gun owners in Troutdale and Gresham who are challenging the law.
He says the most controversial part of the law is an easy-to-miss sentence in the preamble: "This ordinance will apply countywide unless a city within Multnomah County enacts separate legislation on this same subject matter."
"That's never been done before," McCain said.
Six cities sit fully within Multnomah County, and two straddle the county line. McCain says the Oregon Constitution gives those cities the ability to come up with their own laws. He thinks the county's gun law should only be enforced outside those city limits, in unincorporated areas.
"The county is claiming that we have wall-to-wall jurisdiction now," he says. "We can impose our will on cities. All 730,000 people in the county are now under our thumb."
Whether the gun ordinance applies in the cities is a critical question for both law enforcement and for gun owners. That's because more than 95 percent of the people in Multnomah County also live in a city like Portland, Fairview or Gresham.
Paul Diller, a professor of law at Willamette University who studies local governments, says the case raises an interesting question.
"I can't think of a precedent where county and city authority have clashed like this."
Diller says the Oregon Constitution gives both cities and counties the right to self-rule. And the law hasn't clarified how county laws apply within city limits.
He says the case could inspire other lawsuits pushing back against recent county ordinances, like the ban on growing GMO crops in Jackson County in Southern Oregon. He says a farmer in Medford could claim the ban doesn't apply within the city limits.
"So it's not just in the gun sphere, in the firearms area, where this issue might come up in a prominent way," Diller says.
A Multnomah county spokesman said he could not comment on the lawsuit until after the trial. In legal briefs, the county calls the gun ordinance "a proper exercise of county legislative authority." The case goes to trail Wednesday morning.
This story originally appeared on Oregon Public Broadcasting.