I recently returned from New York. At a dinner party I was introduced as a guy who lives on a ranch near Manhattan--Manhattan, Montana that is.

Chuckling, a man to my left said, "Montana, I hear that's a wild and woolly place. You must have a lot of car jackings".

"Car jackings?"

"You know," he continued. "Some stranger threatens you in a parking lot or stop light and takes your car."

"No, I've never heard of one back home and don't expect to--unless the guy was vying for the Darwin Award". (See Darwin Award web site www.darwinawards.com.)

"What's a Darwin Award?", he inquired.

I advised him that was the prize annually given to the person who has done the most to improve the human gene pool in a stupendously stupid act resulting in his death and hence removal from the gene pool.

"Well," he inquired, "are there a lot of dead bodies in parking lots and stop lights?"

No, I've never heard of a car jacker being killed in Montana. They know better than to attempt to hijack a vehicle. It's like on our ranch. For years we lost a lot of sheep and lambs to coyotes. Then, twenty years ago we got two livestock guard dogs; Komondor was the breed. Annual predation dropped from over five percent to under one percent. And we never found a dead coyote. They knew better than to attack. In a sense, we armed the sheep.

In a state where nearly one out of each 100 adults is a licensed firearm dealer and many drivers are insured by both Allstate and Smith & Wesson, the life expectancy of a car jacker would be low. While most criminals are stupid, they consider the costs and benefits of their actions.

This is the theme of an important, persuasive, and reviled book by John Lott of Yale's School of Law. While working as staff economist for the U.S. Sentencing commission, John became interested in the deterrence effect of an armed citizenry. Lott's book is the most thorough empirical analysis of the relationship between gun ownership and the incidence of crime ever undertaken.

There is probably no subject in which empirical data and logical argument have less impact upon well educated citizens than gun control and the Second Amendment. It states: "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear arms will not be infringed".

There is a fundamental shift among legal scholars toward accepting individuals' rights to keep and bear arms. They have re-examined the historical record, including Jefferson's and Madison's correspondence. Yet, many liberals still deny the Second Amendment's clear meaning and believe it is a terrible mistake.

In their views, with a benevolent, protective, vigilant, and intrusive government, the citizens need not be armed. Aside from gated communities and traditionally peaceful neighborhoods, these conditions seldom prevail.

In this arena ideology trumps logic and data. Regardless, facts are stubborn things and data accumulates. Experiments buttress Lott's argument. Here are the results of a recent gun control trial.

Last year, Australian gun owners were forced to surrender for destruction 640,381 personal firearms (including semiautomatic .22 rifles and shotguns.) This program cost the Australian government more than $500 million. Browning A-5 shotguns and valuable collectors' items were surrendered up to be crushed into scrap.

The Australian prime minister decreed, "Self-defense is not a reason for owning a firearm". However, there has been a dramatic increase in break-ins and assaults of the elderly, those left with feeble protection.

Keith Tidswell of Australia's Sporting Shooters Association reports the results. His reports, based on a full 12 months of data:

Australia-wide:

* homicides up 3.2 percent;

* armed-robberies up 44 percent;

In the state of Victoria, homicides-with-firearms are up 300 percent.

Let's go back to New York. Although relatively few people in Manhattan, New York own cars, those in adjacent cities and suburbs drive into the city. Here's an idea for them.

Order a magnetic sign, with printing on both sides, to stick on the doors of their cars. When they park, they expose the message, "This is a gun free car." When they enter the car, they would turn over the sign. The flip side would read, "This car is insured by Smith & Wesson".

If this idea is widely adopted, and demonstrated, we could expect the car jacking rate in Manhattan, NY to move toward that in Manhattan, MT.