http://m.motherjones.com/mojo/2013/03/s ... und-checks
That's why simple things that can delay access to a gun, like mandatory background checks for all handgun purchases—including private sales—like those that would be required by a new bill recently passed by a Senate committee, can make a big difference in preventing suicide. States with such a requirement have a gun suicide rate 50 percent lower than states that don't, even when their non-gun suicide rates are about the same.