For all the faults of the reporting of crimes, the assumptions being made are not nearly as logically sound as the assumptions seem to assert.  Exposure to leaded gas affects brain development, and impulse control.  Alcohol for me also affect my impulse control, and I become more aggressive, and in my youth, violent&#x2F;destructive.  But at no point is my moral centre so far off that murder becomes a viable option.  So the assumption that violent crime rates matches murder rates proportionally, is throwing another unknown variable into the mix, and attempting to make that appear far more rational than it it.