You're asking for a logical explanation to an illogical "anti-crime" gun control law. You're more likely to get a rational answer as to why gravity exists.
The sad truth is that the only TRUE reason for 99.9% of the gun control laws is not to combat crime, but rather to disarm the populace. You see, those people who wish to impose their will upon us know the same simple truth that we do: that freedom and the ability for armed resistance go hand in hand. Our founding fathers (in the US) knew this which is why the Second Amendment exists (and why it is second only to the freedom of speech which gives the people the power of political dissent).
The premise that gun control laws can prevent crime is so patently absurd, it is a wonder that anyone actually falls for it. As if a criminal who intends to commit a violent illegal act cares a hoot about breaking gun laws. Such gun control laws only go to illustrate that the vast majority of Americans are ignorant, mentally lazy, and/or lack the educational training for the independent critical analysis of facts. (And now you know why the government-mandated and controlled public school systems are dumbing-down education programs and turning the classrooms into socialist indoctrination camps.)
There are basically three types of anti-gunner: the tyrant, the panderer, and the reactionary.
The tyrant is an elitist who believes that his or her inherent "superiority" grants them the power to control all aspects of your life (and death). Hillary Clinton, Gore, Schumer, Boxer, DiFi, Waxman, Hitler, Rosie O'Donnell, and many others fall into this category.
The panderer rides the wave of popular opinion in order to further their own agenda of power and/or wealth. They don't really care about gun-control issues (or any others for that matter); they just seize upon the "will of the people" to advance themselves. Bill Clinton is the epitome of the panderer politician. All of his "agenda issues" were really pushed from behind the scenes by his wife and VP.
The reactionary is typically someone who has suffered some personal tragedy (and is usually wholly or partly responsible for that tragedy); now he or she is on a crusade to change society to "prevent others from going through the pain (they're) going through." They do this primarily because it absolves them of the guilt for their own personal irresponsibility in the tragedy ("it wasn't my fault, it was society's fault: there was no law to prevent it"). Jack Scott and Carole Price fit quite well into this category.
None of these people care about our Constitution (the ultimate law of the land in the US), nor do they care about your liberty.