I touched on this earlier today. But Glenn Kessler’s examination of one of the leading arguments the “gun rights” crowd uses against expanded background checks deserves its own post, and says something important about the broader debate.

You often hear Republicans arguing that we don’t need to expand background checks because we should “enforce current laws first before making new ones.” The claim Kessler looked at was a narrower version of this: Lindsey Graham’s assertion that of the 9,000 people who failed a background check in 2010, “none of them were prosecuted.”

Kessler found that this was flatly false. But he went on to examine the larger argument from the right, i.e., the idea that we should better enforce the current law before expanding it. This is based on the idea that there have been few prosecutions of those who have failed background checks.

To summarize, Kessler found that there are reasons that it looks like there are few such prosecutions. They involve things like prosecutorial discretion in allotting resources, the difficulty of prosecuting such cases, and the lack of reliable national data on how many such prosecutions there are on the local level. Despite all this, it turns out that there are more prosecutions than conservatives imply. We just don’t know how many. As Kessler concludes:

It would be helpful if a comprehensive nationwide survey on fugitive prosecutions had been done, but the available evidence shows that at least some fugitives are identified through the background system and subsequently pursued at the state level for prosecution.

It’s hard to imagine Republicans and conservatives would say those prosecutions are a bad thing, which alone confirms that background checks do work. But the more important point to understand here is that this talking point is explicitly designed to confuse the debate.

The purpose of background checks is to interrupt the transfer of guns to people prohibited from having them. If and when that happens, the policy has had its intended effect — whether or not those checks result in an arrest or conviction later. Even if you believe we should do a better job in following up on such convictions, that does not preclude us from also acting to tighten the screen further by expanding background checks to more sales.

Indeed, implicit in the right’s talking point is the idea that background checks that stop prohibited people from getting guns is a good thing — as long as they’re followed up by an effort at an arrest. Obviously Republicans believe this because they think prohibited parties who have failed a background check will continue to try to acquire a gun. But the loophole in the law is a leading reason they are sometimes able to succeed at this, which is why the loophole needs to be closed. The fact that prohibited people will continue trying to break the law no matter what we do is not an argument against making it harder for them to break the law.

The “enforce current laws first” argument creates a false choice. And it’s a self refuting one, too. But on first hearing, it sounds like it makes sense. The gun rights crowd is very good at making extremely reasonable sounding arguments that are actually designed to sow confusion and obfuscate the true nature of the actual policy argument we’re having.