Counting Mexico's Guns

Obama says 90% are from the US, Fox says 17%, so, who's right?

From FactCheck: (click for full article and stats)
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Counting Mexico's Guns
April 17, 2009
Updated: April 22, 2009

President Obama says 90 percent of Mexico's recovered crime guns come from the U.S. That's not what the statistics show.

Summary
There's no dispute that thousands of handguns, military-style rifles and other firearms are purchased in the U.S. and end up in the hands of Mexican criminals each year. It's relatively easy to buy such guns legally in Texas and other border states and to smuggle them across.

But is it true, as President Obama said, that "[m]ore than 90 percent of the guns recovered in Mexico come from the United States?" Government statistics don’t actually support that claim.

The figure represents only the percentage of crime guns that have been submitted by Mexican officials and traced by U.S. officials. We can find no hard data on the total number of guns actually "recovered in Mexico," but U.S. and Mexican officials both say that Mexico recovers more guns than it submits for tracing. Therefore, the percentage of guns "recovered" that are traced to U.S. sources necessarily is less than 90 percent. Where do the others come from? U.S. officials can’t say.

Fox News has put the percentage of guns that have been traced to U.S. sources 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 that have been traced to U.S. sources is more than double what Fox News has reported.
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