Criminals don't need guns when simple tools are so much easier and cheaper to acquire. http://www.nbc4.com/news/14062857/de...l?dl=mainclick
If the hammer is concealed, is it a concealed weapon? Is it permissible to open carry a hammer in D.C.? We have to ban these tools as they are inherently dangerous. The 2nd Amendment does not specify hammer, does it?