The ruling -- which would come from Judge Roger Benitez -- is believed to be imminent, according to Kostas Moros, a lawyer representing the California Rifle and Pistol Association. Moros said the final response briefs in the cases are due on Tuesday and Benitez could rule any time after that.
Advocates on both sides of the gun debate issue say they expect Benitez, who is known for ruling against California's gun control laws, will decide to strike down the three-decades long law.
"We would see this as a win," Rick Travis, the legislative director for the California Rifle and Pistol Association, a gun rights lobbying group, told ABC7 News.
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Still, Travis said the decision is unlikely to lead to any immediate change in the sale of guns in California.
"Californians have this idea that when they hear the news, that this is going to change overnight. This isn't," Travis said. "No matter what happens either way with the decision nothing's going to change for the foreseeable future. And when I say that, I mean for years."
Travis said the decision will be appealed to the 9th Circuit Superior Court and from there, potentially, all the way up to the Supreme Court.
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Governor Newsom warned about the likely ruling earlier this month while announcing new gun control legislation after the Half Moon Bay and Monterey Park shootings.
"I look forward to Judge Benitez's decision. It's already written," Newsom predicted. "He's likely to overturn our assault weapons ban. Stay tuned. That's a preview of things to come in the next few weeks."
"Large capacity magazine clips. That will likely also be thrown out by the same ideologues," Newsom added.
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In addition to the assault weapons ban, Judge Benitez is also hearing a case on California's ban on certain magazines.
If Benitez does overturn the assault weapons ban, it would not be his first time. He struck down the law in 2021. However, a higher court reinstated the law.
But Travis says this time is different. The decision would be the first to come after the Supreme Court's Bruen decision last year that overturned a New York gun control law and made it easier to argue laws restricting guns are unconstitutional.
Travis said that ruling gives gun rights groups a better chance of actually overturning California's assault weapons ban.
"It forced you to have to go back to the original text, the history based off of that text, and what is common use at this time," Travis said of the new standard set by the Bruen decision. "And those are the things that help set the standard of how a judge or judges, in case of a panel, have to review anything under the Second Amendment."
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Newsom recently condemned the Bruen ruling, which says gun control laws can be found unconstitutional unless the government could show they were consistent with the nation's historical tradition of firearms regulation, going back to the country's founding. Newsom said it doesn't take into account how guns, and the country, have evolved.
"Presumably, somehow equating those that are doing the same with AR-15s or other assault weapons to those with muskets," Newsom said. "I mean, it's perverse. The whole thing is perverse."
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But it's that new standard -- along with a majority conservative Supreme Court -- that has gun rights groups feeling empowered to take on California gun control laws.
Travis believes the assault weapons ban case will be brought to the Supreme Court.
"I think most of these laws with firearms in California, in this space, that's where they're going to be going," he said.
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