NOURIEL ROUBINI, a guy who knows a lot about risk, tweets in favour of mandatory liability insurance for gun owners:

If we had liability insurance on guns, as we do 4 cars, we will see which insurance company would insure at which price folks with arsenals

It's an idea that seems to be gathering a bit of steam.

At Forbes.com, John Wasik lays out the logic behind treating firearm deaths as a market externality to be compensated via insurance, as we do with cars: "Those most at risk to commit a gun crime would be known to the actuaries doing the research for insurers... An 80-year-old married woman in Fort Lauderdale would get a great rate. A 20-year-old in inner-city Chicago wouldn’t be able to afford it. A 32-year-old man with a record of drunk driving and domestic violence would have a similar problem."

Robert Cyran and Reynolds Holding write that mandatory liability insurance is a measure that could pass Supreme Court muster where other restrictions might fail: "[T]here’s a strong argument that damage caused by firearms gives the government a 'compelling interest' to require insurance, the test for infringing a constitutional right."

The first objection that leapt to my mind was that given that 9,000 people per year are murdered with firearms in America, and that essentially every one of those killings entails a wrongful death that could be grounds for a suit, liability insurance for firearms might be so prohibitively expensive that no one would be able to afford it. But it looks like this probably isn't the case.

The National Rifle Association already offers "excess personal liability and self-defence" coverage to its members, and according to their website it seems $100,000 worth of insurance costs just $165 per year; $250,000 worth is $254. That may seem too low a value to put on someone's life, but it's a lot better than nothing, and as Mr Wasik says, the private insurance market will likely do a very good job of discriminating between gun owners who pose different levels of risk.

This isn't a substitute for other popular gun-control measures, such as limitations on magazine capacity, universal background checks (which even NRA members support) and so forth. But given the limitations on possible gun control measures in a country where the Supreme Court holds individual gun ownership for home self-defence to be a constitutionally protected right, and where there may be 300m firearms already in circulation, it seems like a good place to start.

For that matter, there's no reason why we should wait for the federal government to impose these policies. States with strong pro-gun-control politics could start passing mandatory firearm-insurance laws right now. Apparently an effort to do so in Illinois in 2009 ran aground due to opposition from gun organisations and right-wing media, but the politics of the issue would probably be rather different today.

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