Earlier this week, we talked with the Independence Institute's Dave Kopel about a lawsuit against Colorado's new gun-control laws supported by 55 sheriffs throughout the state; see the suit and more below.

Today brings a rebuttal from Colorado Ceasefire's Tom Mauser, who became a gun-control advocate after his son Daniel Mauser was murdered in the 1999 Columbine massacre. He doesn't think much of the sheriffs' arguments.

"It's clear they didn't want these laws passed in the first place," says Mauser, a Colorado Ceasefire board member who serves as the organization's spokesman, "so it's not a surprise they'd attack them on any basis they could."

One portion of the lawsuit contends that the state's ban on magazines that hold more than fifteen rounds violates the Americans with Disabilities Act. As Kopel told us, "The ADA requires state and local governments to make accommodations for disabled people, particularly in regard to major life activities. And many disabled people have less ability when they're attacked in their home to retreat to a point of safety or get behind cover from which they can change a magazine. They may have less mobility, or some might have only one arm, for example. So it's more difficult for them to change magazines than do other people -- and therefore, even if the magazine ban were constitutional in general, which we argue it is not, the people with relevant disabilities are entitled to reasonable accommodations to larger magazines."

Mauser's response? "He's essentially saying it takes more than fifteen bullets at one time to defend yourself, and there's no evidence to show that. If that was the case, you could argue that the disabled should really have a weapon that can fire 100 rounds. Yet he acknowledges that they're not trying to make the case for 100 rounds."

Indeed, Kopel said if the lawsuit had been about magazines holding that number of rounds, rather than those in the twenty-to-thirty range, a number of the 55 sheriffs currently supporting the complaint likely wouldn't have offered their endorsement.

Kopel also maintains that a line in the bill nixing magazines that can be readily converted to fit more rounds results in a "de facto gun even broader than the one that was struck down in D.C. v. Heller," a Supreme Court case that tackled prohibitions against handguns in the District of Columbia. (We've included that ruling below as well.) By his estimate, 82 percent of handguns and at least one-third of rifles manufactured in the U.S. use such magazines. In his view, that meets the so-called "common-use test" featured in the D.C. v. Heller judgment.

To Mauser, this assertion is suspect because "the Supreme Court ruling in the D.C. case was about the weapons, not the number of bullets.

"He's trying to say that because these guns commonly carry a thirty-round magazine, that's what makes them common," he goes on. "And while the court ruled that handguns are common, they didn't run on whether a handgun with a thirty-round magazine would be acceptable. They simply didn't do that, so he's trying to stretch -- trying to say that because a number of people have these fifteen- or thirty-round magazines, therefore it's common and should be allowable. And I would disagree with that -- so obviously, he's throwing it to the courts to decide."

Continue for more of our interview with Tom Mauser, plus documents and a video. At the same time, Mauser concurs with Kopel that language suggesting that convertible magazines -- ones with removable base plates or floor plates that can be adapted to hold more rounds -- may be illegal under the new legislation. He sees it as an issue in need of tackling.

"That's something the attorney general tried to address, and we're going to have to continue addressing it," he says. "Personally, I think the way to deal with it is to make magazines that aren't adaptable. We shouldn't easily allow people to overcome the intent of the law by being able to strap a thirty-round magazine on their weapon. But it's clearly a difficult issue, and it may have to go back to the legislature for more consideration about how to deal with it."

By the way, Kopel previously said that both the sponsor of the bill, Representative Rhonda Fields, and the governor's office agreed with him that the bill bans all magazines with removable base plates or floor plates. He backs up this statement by referencing a 9News report from March, on view below, in which Fields says just that and a conversation he had with a representative of Governor John Hickenlooper's staff on the topic.

Also noted as problematic by Kopel are background checks to be done by dealers who will be paid only $10 for a ton of paperwork that could result in severe penalties against such businesses if there are any errors. As a result, Kopel believes that many dealers will decide not to provide such checks -- but Mauser doesn't buy it.

"Back in 2000, when we closed the gun-show loophole, they talked about the same things: 'It will hurt private sales and it will destroy the gun shows because no one will want to do the background checks.' And that hasn't happened. Those were just scare tactics -- and some shops are saying they won't do them because they're being bullied, being pressured to take that position. There's a lot of peer pressure within that community to do everything possible to make these laws look bad.

"If you go to a gun show today and it's a private gun sale, the gun-show operator will get someone to do the background check, because it's in the interest of the business," he continues. "If they want to do business with that person in the future, they'll get a background check done. That's how business operates."

Continue to see more of our interview with Tom Mauser, plus documents and a video. Likewise, Mauser rejects the suggestion that because Fields and other supporters of the measure publicly said the only reason to own a magazine that holds more than fifteen rounds is to kill a lot of people, the bill is based on prejudice against lawful gun owners who would never consider doing anything of the sort.

"This is them trying to make it seem like those who promote these laws don't like gun owners or are against them -- and that's nonsense," he says. "What people are concerned about is the ability of some weapons to mow down people, and the intent of some deranged people to mow down people.

"To me, the challenge to Dave Kopel and the sheriffs is, 'Do you want to make it easy for people to get hold of a gun that can mow a lot of people down?' They seem to want to make it easy. And because they're losing the public-opinion battle, they say we're discriminating against gun owners and casting aspersions as if we're blaming them for bloodshed. And that's just not the case. We're not discriminating against anyone. We simply want to make it more difficult to get these kinds of weapons, not easy."

Look below to see the aforementioned 9News report about the magazine ban, followed by the complaint against the gun laws and D.C. v. Heller, the Supreme Court case mentioned by both Kopel and Mauser.

More from our News archive: "Colorado gun-control laws: Here's why 55 sheriffs think they're illegal."

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