Do gun bans really stop criminals from getting guns? Americans need not look no further than the massive gun battle with armed gangs fighting police and soldiers that took place in Kingston, Jamaica today. At least 30 people were killed in the fighting. It is a huge number for a small island nation of fewer than 3 million people, but unfortunately murder is so common in Jamaica that these murders won't even be noticed in the annual crime numbers.

With Chicago's Mayor Daley again claiming that a gun ban is necessary to keep Chicagoans safe, Jamaica and other countries with gun bans might teach Americans a lesson.

Everyone wants to keep guns away from criminals, but the question is: who is most likely to obey the law? In the case of a ban, every instance we have data for shows that when a ban has been imposed, murder rates rise. In America, people are all to familiar with the increased murder rates in Chicago and Washington, D.C.. But supporters blame those gun control failures on the ease of getting guns in the rest of the country. Yet, even in island nations such as Ireland, the U.K., and Jamaica -- all of which have imposed bans -- their easily defendable borders and lack of obvious neighbors haven't stopped drug gangs from getting either drugs or the guns that they use to protect their valuable product.

Jamaica wasn't always the extremely violent country that it is today (see the figure here). Jamaica experienced large increases in murder rates since enacting a handgun bans in 1974. Since the gun ban, Jamaica’s murder rate has soared to become one of the highest in the world, currently at least double that of other Caribbean countries. Jamaica’s murder rate hasn’t sunk below 10 murders per 100,000 people since the gun ban went into effect.

Even before the recent rampage, Jamaica's murder rate was about six times higher than before the ban went into effect. Indeed, Jamaica's current murder rate is so high -- at about 60 per hundred thousand people -- that 30 additional deaths in one day will barely be noticeable: 30 deaths will only increase the murder rate from about 60 to 61.

Just as Mexico's President Calderon showed last week, it is always easy for politicians to blame crime on guns. The crime data in Jamaica shows the same thing as the crime data in Chicago and Washington have shown. It is the law-abiding, good citizens, not the criminals, who are disarmed by gun bans.

John R. Lott, Jr. is a FoxNews.com contributor. He is an economist and author of "More Guns, Less Crime."(University of Chicago Press, 2010), the third edition of which was published in May."

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