The question is one of negligence calculus, aka The Hand Formula.

en.m.wikipedia.org/wiki/Calculus_of_negligence

I would state the question this way: should a gun maker have a duty to take reasonable steps to ensure the ultimate purchaser will not use it in a crime?

The concept of negligence calculus comes from a case involving what steps a mariner must take to ensure their boat does not breakaway from its mooring and smash the whole marina to all to shit?

The rule was stated:

[T]he owner’s duty, as in other similar situations, to provide against resulting injuries is a function of three variables: (1) The probability that she will break away; (2) the gravity of the resulting injury, if she does; (3) the burden of adequate precautions.

A good example is the duty of a railroad to protect people at road crossings.

Is it enough to have a policy that conducters blow the whistle? Must the railroad ensure that there are gates, lights, and bells, at every crossing? If it is a blind intersection, must the conducter send the engineer down to the roadway to manually wave off any traffic?

1. The probability of the train causing an injury depends on how busy the intersection is. 2. The gravity of train injuries is very serious; I’ve seen it, they chop you up like a fish. 3. The burden of blowing a whistle is minimal, if it’s a remote crossing that might be an adequate precaution; the burden of installing and inspecting crossing devices such as bells and gates is massive, but again the nature damages caused trains is catastrophic.

The evidence a plaintiff puts forth in a civil lawsuit, to a jury of peers, in public, is to say: this is the extent of my injury, these are the circumstances in which I became injured, and this is what the defendant did or did not do to prevent the injury. The question for the jury is, was the defendant’s conduct reasonable?

The thing with guns, not unlike trains, is that second part of the equation: that the nature of resultant injuries are so serious, such as classrooms full of dead kids so blown apart by bullet that it takes DNA identify the bodies, or shopping plazas strewn with dead families who bled out trying to crawl away. You must think of all the injuries, not just the primary victims. The taxpayers of Newtown, Conn. had to build a new elementary school, paying workers’ comp. benefits to town employees spouses and kids that could go on for decades. Hundreds of millions of dollars in damages.

The burden of prevention could be comparatively minimal. Doing a private background check on every purchaser is minimal. Insurance companies do it for every policy they wrote and every claim they adjust. And with data analytics it is easier than ever. Family status, work status, gun and ammo buying habits are apparently the major predictors of whether someone is likely to commit a serious gun crime. Here’s another example: credit scores are apparently a better predictor of driving risk than driving history!

These questions of risk can be analyzed and can be apportioned.

In my view, gun owners and makers should be liable in tort for damages caused by their weapons. This is a matter of the intended use of the product and the privity of contract between the manufacturer and the end purchaser, no different than products liability. People injured by guns should be able to bring the manufacturer before a civil jury and say: these are my injuries, these were the circumstances in which they happened, these are the steps the manufacturer took or did not take to prevent it, and let a jury decide if the steps were reasonable based on the probability that the harm would result and the extent of the burden of avoiding it.

It would be a lot of risk to manufacturers. If found liable, they would be able to sue the end user for contribution, just as in a products liability case; that’s called subrogation.

You can get gun insurance right now but it’s not required, which makes gun owners self insured. Gun makers could get business liability insurance, too; I think most of them self insure right now hough, because they are immune from such lawsuirs, that’s why Remington went bankrupr the shit against it for Sandy Hook went forward, and it was non or under insured.

If end users were required to carry insurance, the risk of damages is on the insurer, which it bears voluntarily in exchange for premiums. This relieves the manufacturers, the end users, and the public. Right now, the communities bear the entirety of the risk, gun owners can buy whatever guns they want, however many they want, and when they’re mental facilities eventually declined to the point of the violent instability, they have no responsibility beyond their net worth.

And, as a matter of principal, even right now, nobody can claim to be a responsible gun owner if they are non or underinsured for damages caused by their gun.