In an April 20 editorial, The Washington Times advanced the “myth” that 17 percent of guns recovered in Mexico have been traced back to the United States. The Times wrote that "[i]t is completely untrue that 90 percent of guns recovered in Mexico are from America. ... Of the ones sent here to be traced, 90 percent turn out to be from America, but most guns recovered in Mexico are not sent here so are not included in the count. Fox News reported that 17 percent is a more accurate number." However, FactCheck.org reported in an April 17 article that “the 17 percent figure is a myth, too. The [Fox News] reporters made some mistaken assumptions about how many guns had actually been traced to U.S. sources. ... The Fox numbers are 'a subset' of the actual total traced to U.S. sources, one official said.” FactCheck.org added that if the rough figure provided by Mexico's attorney general is accurate, the real number is “more than double what Fox news has reported.”

FactCheck.org wrote of Fox News' 17 percent “myth”:

Fox News has put the percentage at only 17 percent, but we find that to be based on a mistaken assumption that throws its figure way off. We can't offer a precise calculation because we know of no hard information on the total number of guns Mexican officials have recovered. But if a rough figure given by Mexico's attorney general is accurate, then the actual percentage of all Mexican crime guns traced to U.S. sources is probably less than half what the president claims, and more than double what Fox news has reported.

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The Myth of 17 Percent

According to a Fox News report, titled “The Myth of 90 Percent”, only “17 percent of guns found at Mexican crime scenes have been traced to the U.S.” But the 17 percent figure is a myth, too. The reporters made some mistaken assumptions about how many guns had actually been traced to U.S. sources.

Fox News reporters William La Jeunesse and Maxim Lott note, quite correctly, that Mexico doesn't submit all the guns it recovers to the U.S. for tracing. Furthermore, Fox reported, this is “because it is obvious from their markings that they do not come from the U.S.” And it quoted a law enforcement official as to why:

Fox News, April 2: “Not every weapon seized in Mexico has a serial number on it that would make it traceable, and the U.S. effort to trace weapons really only extends to weapons that have been in the U.S. market,” Matt Allen, special agent of U.S. Immigration and Customs Enforcement (ICE), told FOX News.

We were able to confirm that with an ATF spokeperson, who said that U.S guns have special markings that make it possible for the organization to trace them. That means that the guns that ATF is given to trace are far from a random sample of all guns recovered. Indeed, it omits those that Mexican officials have reason to believe come from elsewhere, and includes only those guns with a good chance of being traced to U.S. sources.

But the Fox figure of 17 percent is based on a misreading of some confusing House subcommittee testimony by ATF official William Newell. The Fox reporters come up with a figure of 5,114 guns traced to U.S. sources in fiscal 2007 and 2008. That figures to 17.6 percent of the 29,000 figure for guns seized in Mexico, as given by the country's attorney general.

The 5,114 figure is simply wrong. What Newell said quite clearly is that the number of guns submitted to ATF in those two years was 11,055: “3,312 in FY 2007 [and] 7,743 in FY 2008.” Newell also testified, as other ATF officials have done, that 90 percent of the guns traced were determined to have come from the U.S. So based on Newell's testimony, the Fox reporters should have used a figure of 9,950 guns from U.S. sources. That figures out to just over 34 percent of guns recovered, assuming that the 29,000 figure supplied by Mexico's attorney general is correct.

Even that number is too low. At our request, an ATF spokesman gave us more detailed figures for how many guns had been submitted and traced during those two years. Of the guns seized in Mexico and given to ATF for tracing, the agency actually found 95 percent came from U.S. sources in fiscal 2007 and 93 percent in fiscal 2008. That comes to a total of 10,347 guns from U.S. sources for those two years, or 36 percent of what Mexican authorities say they recovered.

The mistake the Fox News reporters made was to focus on some numbers given by Newell and Hoover in separate testimony, regarding numbers of guns traced to specific states. But not all guns traced to the U.S. can be traced to specific states. The Fox numbers are “a subset” of the actual total traced to U.S. sources, one official said.

From the April 20 Washington Times editorial:

It is completely untrue that 90 percent of guns recovered in Mexico are from America. The Mexican government separates guns it confiscates that were made in the United States and sends them here to be traced. U.S. weapons are easy to identify because of clear markings.

Of the ones sent here to be traced, 90 percent turn out to be from America, but most guns recovered in Mexico are not sent here so are not included in the count. Fox News reported that 17 percent is a more accurate number.