^ Well there's the snag. Requiring them to pay out would require a verdict
from a jury that in all likelihood won't hold them any more responsible than has been the case in civil suits against gun owners whose guns were taken or used for ill without their knowledge, consent, or approval for the past two-hundred years.
You can pass laws claiming all sorts of legal responsibilities, but if the jury just doesn't see it then they won't grant an award, and in this case what they need to see is actual responsibility for the final outcome that traces back to an event that occured possibly years earlier and seperated by perhaps half a dozen intermediaries.
For example, one of my friends had his gun safe ripped out of his floor by a Mexican and broken open by the railroad tracks. His personal Glock was removed and then used later that night in an attempt to trade it for hard drugs in a DEA sting operation. Had the DEA not recovered it the gun would've passed through all sorts of hands and ended up Lord knows where and used for God knows what.
You can write a law that say he's legally liable for whatever final outcome occured, but how on Earth are you going to convince a jury that he was in any way to blame, or even remotely connected to a crime other than as the victim of a robbery? Jurors are not idiots.
The other problem is that any such finding would set a legal precedent that you
are responsible if teenagers break into your house, steal your beer, steal your car, and then get in some horrible traffic accident with lots of fatalities. In fact, you'd be responsible to the tune of potentially millions of dollars. If they stole your laptop and used it to hack into something, you'd be legally responsible. If you sold someone a laptop and they used it for a crime, you'd be legally responsible. All this due to precedent.
As it stands now, if a jury thinks you were willfully reckless or in cahoots with the perpetrator, they can already
hold you liable. If prosecutors think you knowingly
sold a gun to a criminal or sold it knowing it would be used in a criminal enterprise, they can already
charge you with a crime.
The insurance angle doesn't actually add anything, and most gun owners - and home owners, already have insurance that would cover such things. The other problem is that unlike what is hoped for, the insurance rates cannot reflect the actual individual risk or the companies would be sued for bias or discrimination because guns in bad, low income neighborhoods are vastly more likely to be stolen or misused than a gun on a farm, affluent suburb, or gated community.
And the whole idea invites Constitutional scrutiny because you could also require $200 insurance to cover the risk of getting electrocuted in a voting booth, or require insurance to cover costs of illegal searches and seizures, insurance against the risk of being thrown in jail without charges, insurance against being forced to provide free room and board to soldiers, insurance against having your property seized under imminent domain, and of course insurance against libel suits if you want to print anything or post something on the Internet.