Clearly, some criminals obey some laws some of the time; this is the nature of incentive explicit in law enforcement. Even at the margins, this is valuable. Even imperfect efforts to restrict gun availability to high-risk people can reduce illegal gun use on the margin, even if these regulatory barriers can be overcome in a number of ways by those who are determined to obtain a gun. We have one of two mechanisms to explain the decrease in violent crime following gun control: either potential criminals are deterred from crime, or existing criminals are deterred from crime. Either way, you have gun reform that has produced meaningful, substantive improvements in the metrics society should care about. If it’s not clear that laws have the capacity to induce changes in behavior, I won’t be able to improve upon that position.
By definition, criminals don’t follow laws. This is no more a meaningful statement about social realities than the observation that dogs bark or cats meow. Every law could be refuted, and societies would swiftly descend into anarchy if it weren’t for reasonable policymakers. Laws against rape, murder, and theft, for example, are never followed by rapists, murderers, and thieves, but the fact that such people exist in society is the reason behind such regulations in the first place.
Among gun advocates forwarding this line of argument, there seems to be a serious lapse in moral intuition that privileges expediency over human lives. To think that the minor inconvenience of gun reforms such as background checks, waiting periods, and assault weapon bans is more burdensome than the death of thousands of innocent civilians each year reflects a mis-calibrated sense of what matters in the world.
Albert Einstein once said no problem can be solved from the same level of consciousness that created it. If your reason for supporting gun ownership involves loyalty to a document written hundreds of years ago by slave-owning cross-dressers who pooped in holes, you have some explaining to do.