How the NRA et al suppressed research into gun violence: http://jama.jamanetwork.com/article.aspx?articleid=1487470.
Which includes references to articles including:
People carrying a gun 5x more likely to be shot than the unarmed: http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.2008.143099
Purchase of a gun doubles risk of death from suicide or homicide: http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.87.6.974
Research of that sort can no longer be done because of federal and state restrictions won by the gun lobby.
Doug