Scenes from BluCore, a shooting range in Lakewood, for our 2013 post " New to Guns, a Reporter Shoots for the First Time — With an AR-15 ."

Jon Caldara's federal lawsuit against Boulder's assault-weapons ban isn't the only attempt to shoot down the ordinance. A fresh complaint filed by the Colorado State Shooting Association, among others, and backed by the National Rifle Association takes aim at state court in an attempt to double the prospects of the ordinance being killed.

"We're trying on another front," notes Richard Westfall, the attorney behind the latest lawsuit, filed in Boulder County District Court, "and hopefully, one of us will be successful. We support their effort, but we focus on the state preemption issue."

Westfall adds the following explanation: "The Colorado General Assembly identifies firearms issues as matters of statewide concern. So when there were questions about local jurisdictions having conflicting gun laws, they weighed in and created a very comprehensive preemption statute that basically bans local jurisdictions from engaging in this kind of piecemeal regulation of firearms."

The Colorado Criminal Code "permits ownership of 'assault weapons,'" the document points out. "Colorado state law merely prohibits 'dangerous weapons' (including firearm silencers, machine guns, short shotguns, short rifles and ballistic knives) and 'illegal weapons' (including blackjacks, gas guns, and metallic knuckles)."

Anthony Fabian heads the Colorado State Shooting Association. ajfabianlaw.com

As Westfall reads the statute, he sees it as clear evidence that "local jurisdictions have been told they aren't supposed to wade into this area."

But others have, as he acknowledges. "The last big fight we had on this was with Denver," he notes, referencing a controversy that reached the Colorado Supreme Court in 2006. At that time, Denver's assault-weapons ban survived a challenge because of a highly unusual tie vote: Three justices argued to let the measure stay in place, three called for it to be tossed, and the seventh, Alison Eid, recused herself because she'd argued against Denver on the subject as part of her previous job as the state's solicitor general.

Because of this deadlock, Westfall says, "There's no precedent either way. But I think Denver's arguments were much stronger than Boulder's arguments. Boulder is on far weaker ground."

In addition, Westfall and company are receiving powerful assistance from the National Rifle Association Institute for Legislative Action.

The organization's executive director, Chris W. Cox, said in a statement, "Prohibiting law-abiding 18-20 year old adults from purchasing firearms and banning some of the most commonly used self-defense firearms in America will do nothing to improve public safety. Gun control only makes it harder for law-abiding citizens to protect and defend themselves. The NRA will do all we can to restore the Second Amendment rights of Boulder's law-abiding citizens."

Echoing these thoughts was Anthony Fabian, executive director of the CSSA. He referred our inquiry to Westfall, but in the NRA's release, he's quoted as saying, "We will not stand by and allow the misguided gun control extremists on the city council to strip us of our rights. We are grateful for the NRA‘s support of our lawsuit and look forward to restoring the rights of Boulder's law-abiding citizens."

Boulder officials are confident their ordinance will stand up to legal challenges. In May, Boulder Mayor Suzanne Jones told us, "Our ordinance is based on a provision of the Colorado state constitution that gives home-rule cities the power to supersede state law on matters of local concern."

Figuring out who's right is likely to take some time. "I'm sure this will eventually go to the Colorado Supreme Court," Westfall acknowledges. But in his view, "The law is clear: Boulder isn't supposed to do what Boulder did."

Click to read Colorado State Shooting Association, et al., v. the City of Boulder.