Less than a month after a mass shooting in California, San Jose is considering a proposal that would make it the first city in the U.S. to require gun owners to carry liability insurance.

Mayor Sam Liccardo, who introduced the legislation last week, says the mandate would follow the “harm reduction” approach used with car insurance: rewarding safe behavior, while covering the cost of accidents and neglect.

“Insurance can force people to engage in safer behavior,” he says. “Whether they get good driver discounts for airbags or discounts for having a gun safe and for having a child-safe lock.”

On July 28, a gunman killed three people and injured 12 more at the Gilroy Garlic Festival, just south of San Jose. Two of the victims, 6-year-old Stephen Romero and 13-year-old Keyla Salazar, were from San Jose.

While Liccardo wants the federal government to ban assault weapons, he’s called this proposed city ordinance a necessary action in the interim.

“There's no question that this measure will not suddenly stop gun violence,” he says, “but at least in the city of San Jose, we're going to stop making the public pay for it.”

The proposal comes in the wake of three high-profile, fatal shootings – Gilroy, El Paso and Dayton – and in a moment when the fight for gun control legislation has gained some steam. But the idea has been around for decades, and similar legislation has been proposed — though not passed — in at least half a dozen states, including New York, Hawaii and North Carolina.

Under Liccardo’s proposal, liability would cover accidental shootings and acts committed by someone who gained access to the gun unlawfully, though insurance would not cover intentional shootings by the gun's owner. Anyone who couldn’t afford or find the insurance would be required to contribute to a public fund, which would go toward the public costs of gun violence.

Proponents say it’s a common sense, market-based solution to reduce gun violence and defray the cost of tens of thousands of deaths — and many more injuries — each year. Critics worry about increasing illegal gun ownership and violating a constitutional right.

“While the Second Amendment protects the right of individuals to keep and bear arms, it does not compel taxpayers to subsidize the cost of that choice,” Liccardo argues. “And right now, taxpayers are paying an extraordinary public health bill for gun violence.”

According to the Giffords Law Center for to Prevent Gun Violence, a San Francisco-based advocacy group, gun violence costs the U.S. economy at least $229 billion every year, half of which is borne by tax payers. Those costs include bills from emergency responders — police, fire departments, emergency rooms — as well as psychological support after shootings.

Others argue that gun insurance might not be a simple solution. Russ Roberts, a research fellow at the Hoover Institution and host of EconTalk, told NPR in 2013 that the cost of insurance would drive away “honest, law-abiding people” from owning guns while increasing purchases of illegal arms.

“Many people already buy and own guns illegally without license or registration,” Roberts said. “Adding the cost of insurance would further discourage honest gun ownership. That would make matters worse, not better.”

But proponents argue that insurance sellers would be able to accurately estimate the risks carried by different gun owners and offer discounts for low-risk owners and penalties for high-risk owners, including young people like the 19-year-old shooter in Gilroy.

Just like how car insurance is expensive for young drivers, Liccardo says, premiums could help ensure more of the cost falls on “folks who should not be getting access to guns” in the first place.