Firearms are used in a large proportion of the violent crimes of robbery, assault, and murder. The widespread availability of firearms, particularly handguns, has frequently received part of the blame for the extraordinarily high rates of violent crimes in the United States, and the violent crime wave of the 1965-1975 decade may have been fueled in part by the growth in the availa­ bility of handguns in urban areas. Advocates of stringent gun control have long argued that the adoption of a program which made it more costly or timeconsuming or legally risky for criminals to obtain guns would have the effect of reducing the amount and seriousness of violent crimes (see Newton and Zimring, 1969).

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