For those who want to dig deeper: Here's a closer look at the sources behind the stats I examined, some examples of where they were published and a summary of the criticism on each.
Claim: Gun violence costs the U.S. $100 billion annually. It's costing this country over $100 billion a year on those victims that do survive and not even counting the 30,000 people that are killed each year from gun violence, whether it's suicide, whether it's accidental or whether it's homicide. New York Democratic Rep. Carolyn McCarthy, on CNBC That number originated in research by Duke economist Philip J. Cook and Georgetown public- policy professor Jens Ludwig. The researchers used a technique called contingent valuation, in which they surveyed respondents about how much they would be willing to pay for a 30% reduction in gun violence. University of Chicago Law professor and noted libertarian Richard A. Epstein explains and critiques contingent valuation in this paper, entitled "The Regrettable Necessity of Contingent Valuation." In an earlier study, Profs. Cook and Ludwig estimated the direct medical cost of gun injuries at $2.3 billion, using mid-'90s stats, for a 1999 paper in the Journal of the American Medical Association. That number was cited in a column about the Virginia Tech shootings in the Independent of the U.K. Claim: The U.S. has the most gun murders per capita in the Western world. The risk of being killed by a firearm in the US is higher than in any other Western nation. There are no recent statistics available but UN figures from 2000 showed for every 10,000 Americans, 0.3 were killed by firearms, compared with 0.01 in the UK where handgun ownership was banned in 1997." BBC News; repeated in the Yorkshire Post There are, in fact, more-recent statistics available: the Eighth United Nations Survey on Crime Trends and the Operations of Criminal Justice Systems, covering 2001 and 2002. Table 2.4 shows the rate of homicide by firearms for the U.S. and the 64 other countries that provided data for the survey. The ninth U.N. survey got responses from just 71 nations, a list that didn't include the U.S. More data on murders in the U.S., by firearm and other means, are available at the Centers for Disease Control and Prevention's Web site. Claim: U.S. citizens use guns 2.5 million times yearly in defense against crime. The Second Amendment Foundation notes that firearms are used defensively an estimated 2.5 million times every year, four times more than criminal uses. This represents some 2,575 lives protected and saved for every life lost to a gun. Alan Caruba of the conservative National Anxiety Center, in a syndicated column appearing in the Tucson Citizen and several other Web sites The number originates in research conducted by Florida State criminologists Gary Kleck and Marc Gertz. Profs. Cook and Ludwig argue that the number is inflated, in an analysis of a Police Foundation-sponsored survey they conducted that found similar results. Here's a Kleck paper rebutting their criticism. GunCite, which opposes Gun Control, rounds up criticisms of Prof. Kleck and his responses. Claim: States that have expanded citizens' rights to carry concealed weapons have far fewer mass shootings. [John] Lott and Bill Landes of the University of Chicago law school examined multiple-victim public shootings in the U.S. from 1977 to 1999 and found that when states passed right-to-carry laws, the rate of multiple victim public shootings fell by 60%. Deaths and injuries from multiple-victim public shootings fell even more an average of 78% as the remaining incidents tended to involve fewer victims per attack. John Fund, OpinionJournal.com's Political Diary; also cited by Wall Street Journal columnist Holman W. Jenkins Jr., in the Washington Times and on WorldNetDaily The research by John Lott, Jr., now a visiting professor at State University of New York, Binghamton, and University of Chicago economist William Landes can be found here. Three other researchers' study, published in 2002 in the journal Homicide Studies, failed to replicate the findings. One author of this study, William & Mary economist Carl Moody, said that a key difference is the studies' use of different statistical models. (Explaining these is beyond the scope of this blog, but you can read more about the negative binomial model, used in the later study, and the Poisson model, used by Profs. Lott and Landes.) Prof. Lott has published several other studies that suggest concealed-carry laws help reduce gun violence. His studies are collected here. A National Academy of Sciences report in 2004 disputed some of his findings. ------------------------------------------------------------------------------------------------------------------ [The Column] THE NUMBERS GUY Carl Bialik Gun-Policy Advocates On Both Sides of Issue Push Dubious Figures April 20, 2007; Page B1 The Virginia Tech shootings have reignited the gun-control debate, with both sides marshalling suspect numbers. Gun violence "is costing this country over $100 billion a year," New York Rep. Carolyn McCarthy, who is pushing tougher gun-control laws, said this week on CNBC, citing the gun-control advocacy group Brady Campaign. The Brady Campaign, in turn, cites research by Duke economist Philip J. Cook and Georgetown public-policy professor Jens Ludwig. But the 2001 estimate, based on a 1998 phone survey, isn't a direct measure of cost. The researchers used a technique called contingent valuation, in which they surveyed respondents about how much they'd pay for a 30% reduction in gun violence. Extrapolating the survey results to the general population, they concluded that Americans are willing to pay $24.5 billion for that outcome. Extending that to a theoretical 100% reduction of gun violence, and factoring in the costs of suicide and injury by firearm, Profs. Cook and Ludwig arrive at $100 billion. WHAT DO YOU THINK? [Numbers Guy] Discuss this column on Carl's blog, and read daily dispatches on the numbers behind the news, at WSJ.com/NumbersGuy. The researchers themselves noted drawbacks to their technique. They were measuring willingness to pay for a 30% decrease -- it isn't clear whether people would pay at the same rate for further reductions. More fundamentally, the willingness-to-pay, or WTP, method assumes survey respondents can quantify the value of a public good and trusts them to give honest answers to a hypothetical that may prod them to present themselves favorably. Most economists agree "that none of the available methods for measuring WTP are entirely satisfactory," Profs. Cook and Ludwig write in their paper. Another argument for gun control: The U.S. has the most gun murders per capita in the Western world (three of 100,000 people annually). That claim holds if the Western world is defined as the U.S. and Western Europe. If Latin America and Eastern Europe are included, then Slovakia, El Salvador, Albania, Costa Rica, Uruguay and Mexico all had higher gun-murder rates in a recent year, according to the latest U.N. figures. The U.N. cautions that the figures are self-reported and, as a basis for comparison between countries, are "highly problematic." Meanwhile, opponents of gun control have written online commentaries claiming that Americans use guns 2.5 million times yearly in defense against crime. The number originates in research, more than a decade old, conducted by Florida State criminologists Gary Kleck and Marc Gertz. They conducted a phone survey of defensive gun use, asking respondents if they, or members of their household, had used guns in self-defense -- and extrapolated their findings to the general population. Defensive gun use, or DGU, doesn't necessarily mean the gun was fired, which happens in relatively few of these incidents, the researchers found. Prof. Kleck cites as corroboration for his findings a 1994 survey conducted by Profs. Cook and Ludwig for the Police Foundation, a Washington law-enforcement research group. Yet those two researchers concluded that their own numbers and Prof. Kleck's are inflated. They explain that surveys can inflate results for rare events. The logic goes like this: Some people who engaged in DGU will deny it to surveyors, while others will invent it. Because DGUs are rare by any estimate, the latter group is a far greater pool of potential liars. So even if the lying rate is lower in that group, false positives could outweigh false negatives. Prof. Kleck countered in an email that surveys typically underestimate controversial behavior and that criticisms of his research show the critics' own bias toward undercounting. Another number that has emerged from the antigun-control camp ties multiple-victim public shootings to restrictions on carrying concealed weapons. John Lott Jr., visiting professor at SUNY, Binghamton, and University of Chicago economist William Landes counted references to multiple public shootings -- more than one killed or wounded at one time -- in the Lexis/Nexis news database for a 2000 book. They matched trends from 1977 to 1999 with right-to-carry laws, and found that when states allowed the carrying of concealed weapons, the rate of these attacks declined by 60%. But another study, published in 2002 in the journal Homicide Studies, found "virtually no support for the hypothesis that the laws increase or reduce the number of mass public shootings." This later study counted only shootings with four or more murders, used FBI crime data to supplement news reports and, unlike the Lott-Landes work, included shootings that were byproducts of other crimes, such as gang murders. Grant Duwe, a researcher on the later study, said the news-archive approach was likely incomplete, because the media don't always give publicity to multiple shootings. Prof. Lott wrote in an email that he counted less-severe incidents to get enough data for statistically significant results. He justifies his exclusion of gang murders because gun usage by chronic criminals "would not be directly affected by the passage of right-to-carry laws." That seems to be precisely the reason to include them for a full picture of the effect of these laws. Of course, the complete picture frequently goes missing in this debate. Email me at [EMAIL PROTECTED] Read daily commentary about numbers and join a discussion with readers at my free blog, WSJ.com/numbersguy. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Upgrade to Adobe ColdFusion MX7 Experience Flex 2 & MX7 integration & create powerful cross-platform RIAs http://www.adobe.com/products/coldfusion/flex2/?sdid=RVJQ Archive: http://www.houseoffusion.com/groups/CF-Community/message.cfm/messageid:233078 Subscription: http://www.houseoffusion.com/groups/CF-Community/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.5
