The mayors of Chicago and New Orleans have filed lawsuits on behalf of their cities against the gun industry, and two similar lawsuits filed on behalf of private citizens are already moving through the courts, with a mixed verdict rendered in one of the private suits. The Chicago suit and the private suits contend that (1) guns are a public nuisance and (2) gun manufacturers knowingly flood cities with more guns than they could expect to sell to law-abiding citizens, thus aiding criminals to obtain firearms. [The New Orleans lawsuit takes a different tack, alleging that without safety devices which would prevent unauthorized users from firing them, guns violate Louisiana's product liability laws.] The mayors argue that the firearms industry should reimburse their cities for the public health and safety costs associated with treating and preventing firearms injuries.

Gun industry critics and organizations working for stricter gun control laws have compared the suits against the gun industry to those against the tobacco industry. But unlike tobacco, guns produce tangible social benefits. More crimes are prevented by guns in the hands of law-abiding citizens every year than are committed with guns. The savings to cities from these defensive gun uses and the general savings to society from gun ownership dwarf the cost to municipalities of gun violence.

Although fewer than half a million violent crimes reported to the police in 1996 involved firearms, more than 15 studies have shown that citizens use guns in self-defense between 764,000 and 3.6 million times annually - often merely showing the weapon. Criminologist Gary Kleck's estimate of about 2.5 million defensive gun uses annually is perhaps the most reasonable.

• About 3,000 criminals are lawfully killed each year by armed civilians - about three times the number killed by police.

• Another 9,000 to 17,000 criminals are wounded by civilians each year.

Research supports the view that the best defense against violence is an armed response. For example:

• Women faced with assault are 2.5 times less likely to suffer serious injury if they respond with a firearm than if they defend themselves with less effective weapons or offer no resistance.

• According to the Department of Justice, only one-fifth of the victims who defended themselves with firearms suffered injury, compared to almost half of those who defended themselves with weapons other than firearms or who had no weapon.

Not only do guns protect potential victims of crime, they also save society money.

• Even using the statistics most favorable to proponents of lawsuits against the gun industry, the benefits to society of defensive gun use are greater than the costs of firearm crimes by at least $90.7 million and perhaps as much as $3.5 billion per year.

• Using more reasonable estimates, the benefits of defensive gun use exceed the costs of firearm crimes by as much as $38.9 billion - an amount equal to about $400 per year for every household in America.

There is evidence that one reason the overall rate of serious crime in the U.S. is at a 20-year low is that since 1987, 22 states have made it easier for private citizens to get what are called concealed carry permits. A recent study by University of Chicago economist John Lott found that:

• Concealed carry laws reduce murder by 8.5 percent, rape by 5 percent and severe assault by 7 percent.

• Had liberalized concealed carry laws prevailed throughout the country in any given year, there would have been 1,600 fewer murders, 4,200 fewer rapes and 60,000 fewer severe assaults.

The lawsuits against gun manufacturers are not just bad public policy, they are also dubious as matters of law. The courts have recognized that firearms are no different from many other potentially dangerous products and have consistently held that legislatures should decide whether guns should be legal and widely available. The suits also seek to reverse the well-established tort law principle that manufacturers are not responsible for the criminal misuse of their products.

To derail these lawsuits, Congress could revive legislation - successfully opposed by trial lawyers and antigun groups in 1998 - that seeks to reduce the number of frivolous product liability lawsuits reaching the courts and to punish litigants who file such suits.

Another option would be for the public to file countersuits against their officials on the grounds of public safety. Though unlikely to be successful, such lawsuits would serve notice that the public opposes attempts at restricting access to guns that would place law-abiding citizens at risk but do nothing to deter criminals or reduce crime.