Substance abuse and violence: cause and consequence.

Substance abuse has been associated with violent behavior for many decades. While the relationship is the same today as it was in the past, the pervasiveness of the association, and the consequences, are more dramatic. There are two ways in which substance abuse is related to violence. First, violence can be and is perpetrated under the influence of substances, and second, violence related to substance abuse stems from the trade in drugs, which is all too often focused in poor and underserved communities. The elimination of the market for drugs, and thus the reduction in the demand for drugs, will bring about a reduction in substance abuse-related violence.