In a society sharply divided over efforts to curb violence and the right to bear arms, both sides of the gun debate seem to agree on at least one thing: a bigger role for the insurance industry to play in a heavily armed society.

But just what that role should be, and whether insurers will choose to accept it, are still very much in dispute.

Lawmakers in at least half a dozen states, including California, Connecticut, Maryland, Massachusetts, New York and Pennsylvania, have proposed legislation this year that would require gun owners to buy liability insurance — much as car owners are required to buy auto insurance. Doing so would give a financial incentive for safe behavior, they hope, as people with less dangerous weapons or safety locks could qualify for lower rates.

"I believe that if we get the private sector and insurance companies involved in gun safety, we can help prevent a number of gun tragedies every year," said David P. Linsky, a Democratic state representative in Massachusetts who wants to require gun owners to buy insurance, which he believes will encourage more responsible behavior and therefore reduce accidental shootings. "Insurance companies are very good at evaluating risk factors and setting their premiums appropriately."

Groups representing gun owners oppose efforts to make insurance mandatory, arguing that law-abiding people should not be forced to buy insurance to exercise their constitutional right to bear arms. But some groups, including the National Rifle Association, endorse voluntary liability policies for their members. And as several states pass laws making it easier for people to carry concealed weapons and use them for self-defense, some gun groups are now selling policies to cover some of the legal costs stemming from self-defense shootings.

The U.S. Concealed Carry Association recently began selling what it calls "Self-Defense Shield." "If you’re forced to justifiably use your gun in self-defense," its website says, "Self-Defense SHIELD will help pay for your expert pro-2nd Amendment lawyer by reimbursing your legal-defense expenses following your acquittal — an ingenious system critical to the arsenal of any responsibly armed citizen."

Some specialized underwriters are reviewing what their policies cover when it comes to shootings, and weighing whether they should offer new types of coverage for gun owners. And as more states pass laws allowing people to bring guns to public venues — including restaurants, bars, churches and the parking lots of their workplaces — some business groups have expressed concerns that they could be held liable for shootings on their properties, which could drive up their insurance costs.

The insurance industry is wary of some of the proposals to require gun owners to buy liability coverage — and particularly of bills, like one that was filed in New York, that would require coverage for damages resulting not just from negligence but also from "willful acts."

Robert P. Hartwig, the president of the Insurance Information Institute, said that insurance generally covers accidents and unintentional acts — not intentional or illegal ones.

"Insurance will cover you if your home burns down in an electrical fire, but it will not cover you if you burn down your own house, and you cannot insure yourself for arson," he said.

Some claims stemming from shootings have been covered by homeowners’ insurance — even by policies that said they do not cover illegal acts.

The families of the two students responsible for the 1999 killings at Columbine High School in Colorado were able to use money from their homeowners’ policies to settle a lawsuit brought by families of most of the victims. In 2001, a California court ordered an insurance company to defend a policyholder whose 16-year-old son shot and killed a friend with a Beretta handgun that he had found in his mother’s coat. But the year before, a North Carolina court ruled that an insurance company did not have to cover the expenses of a policyholder who had shot and wounded a prowler on his property.

Christopher J. Monge, an insurance agent and gun owner in Verona, Wis., recently wrote a book, "The Gun Owner’s Guide to Insurance for Concealed Carry and Self-Defense," which he sells at gun shows. Monge said that the problem with most liability insurance is that it promises coverage only in cases of a gun owner’s negligence, or an accidental shooting — and not if the gun owner shoots someone intentionally in self-defense.

"A negligent act is covered by your liability policy, but if you intentionally shoot somebody, it could be excluded," he said.

So as more states pass self-defense laws, Monge said he found several insurance companies that would specifically offer liability coverage in cases of self-defense, usually in the form of an "umbrella" policy that added a higher level of coverage than the routine coverage for negligence in a homeowners’ policy. An umbrella policy adds coverage for unusual, but potentially expensive, incidents.

But he opposes proposals to make liability insurance mandatory.

"They’re barking up the wrong tree, if you ask me," he said. "Ninety-nine percent of gun owners are going to be safe and not go crazy."

States have been considering mandatory gun insurance bills for years, but no state has passed one yet, said Jon Griffin, a policy associate at the National Conference of State Legislatures. When Illinois considered a bill in 2009, the NRA wrote that it would "put firearms ownership out of reach for many law-abiding Illinoisans." The NRA endorses a policy that offers excess liability coverage — "because accidents do happen no matter how careful you are" — and another that offers "self-defense insurance."

The recent trend of allowing guns in more public places has alarmed some business groups. When Ohio enacted a law allowing guns in bars in 2011, the Ohio Restaurant Association opposed it, writing officials that restaurant owners "expect that this law would be perceived by insurance companies as increasing the risk of injury in establishments that sell alcohol, which of course would result in increased liability insurance costs." Owners have not reported higher premiums because of the new law, said a spokesman for the association, Jarrod A. Clabaugh, but some worry that a shooting incident could drive up their insurance costs.

The current debate over mandatory liability laws is being watched with interest by Nelson Lund, the Patrick Henry Professor of Constitutional Law and the Second Amendment at George Mason University School of Law. Lund proposed the idea of mandatory insurance in a 1987 article in the Alabama Law Review, seeing it as a form of gun control that could be consistent with the constitutional right to bear arms. But Lund said that he had not studied any of the current proposals, and noted that it made a great deal of difference how they are written.

"If this were done, the private insurance market would quickly and efficiently make it prohibitively expensive for people with a record of irresponsible ownership of guns to possess them legally," he wrote in the 1987 article, "but would not impose unreasonable burdens on those who have the self-discipline to exercise their liberty in a responsible fashion."

© 2013 The New York Times Company