The National Instant Criminal Background Check System (NICS), the FBI database to prohibit criminals from purchasing guns, isn’t as functional as it could be. Anything made with human effort is bound to be flawed.

For the Left, the problems with the system are numerous. For example, they regularly gripe about the non-existent “gun show loophole,” which they claim allows criminals to obtain guns. They’re wrong, of course, because gun show purchasers must pass a background check and, therefore, criminals avoid trying to buy guns at gun shows.

So the gun grabbers are getting creative. While they deny the entire idea of natural rights granted by God, they at least acknowledge the rights enshrined in the Second Amendment are too engrained in American culture to attack with an honest piece of legislation. Instead, they chip away when possible and use subterfuge to advance their ideology.

Sen. Tim Kaine (D-VA) recently introduced a bill that does just that. The Responsible Transfer of Firearms Act would increase the risk for a gun seller every time he or she transfers a firearm.

“It would hold a seller or transferor of firearms criminally liable should they fail to demonstrate they took reasonable steps to prevent a weapon from falling into prohibited hands,” Kaine said in a statement. “Why should someone be able to casually place an illegal firearm in the hands of a felon or other prohibited person?”

As the law is written now, it is illegal for a gun seller to transfer a firearm to someone they know or have a “reasonable cause to believe” is prohibited from owning a gun. Sellers already risk being criminally liable if they make a sale to the wrong person. Kaine’s law would toughen up the language of that clause and add “accountability” for when the next act of mass violence occurs.

Private sellers cannot access the NICS and therefore cannot have “taken reasonable steps to determine that the recipient is not legally barred from possessing firearms,” as Kaine’s bill proposes. That led Sean Davis at The Federalist to call the bill “a de facto ban on private, intrastate gun sales.”

Depending on state law, Kaine’s bill may change how a father hands down an heirloom shotgun to his son. Grandfathers could find it that much harder to bequeath to their grandchildren the pistol they carried during the war. And you thought the Left was all about preserving America’s hunting and target-shooting culture.

What will the state accept as proof that a seller took reasonable steps? Kaine says knowing and trusting the person is no longer enough. (Tell that to Barack Obama with Iran.)

To illustrate the flawed assumptions of the gun-grabbing Left, a recent study asked a group of inmates incarcerated in the Cook County Jail near Chicago where they got their firearms. Of the 99 inmates the study asked, the majority of responding inmates said they got their weapon through someone they know. They got them through family members, mutual acquaintances or members of a gang. Only two got their guns from a gun store.

It’s a small sample size, to be sure, but it illustrates an important point: As the NRA reported on the study, “Criminals Don’t Get Guns From Legal Sources.” In fact, they try avoiding anything to do with the NICS. That means only the law-abiding will be burdened by stricter measures.

But the big-government evangelists still put their trust in horses, chariots and universal background checks. This faith should have been shaken after it was revealed that the Charleston murderer — the man who wanted to incite a race war by massacring attendees at a prayer service — passed his background check thanks to human error. A bureaucrat failed to update the system with a pending drug charge.

In the 16 years the system has been in operation, it has stopped more than a million transfers of firearms and explosives. But it’s net isn’t free from human error.

Meanwhile, the numbers of gun owners are rising. The number of background checks that ran through the NICS reached another record high in August, thanks to the knee-jerk rhetoric coming from politicians hours after an exploitable murder.

Leftists’ solutions totally disregard the God-given rights codified in the Constitution. Their policies only advance more control, less security and, in the case of Kaine’s bill, something that intrudes into the lives of every gun-owning American.