The problem with applying risk factor analysis to the law is that the law gains it’s moral authority from its disposition against what is wrong and in favor of what is right. Not every risk factor for a bad event is, independently, morally wrong. For example, littering is wrong, but carrying objects is not wrong, even though it makes littering more likely. Lying in court is wrong, but speaking in court is often necessary, although it makes perjury more likely.
Simply proving that an action or state of affairs carries risk does not say anything for or against its moral justification. Laws regarding the ability of the people to arm themselves need to make sense as a model of individualized justice, not just as a risk-management strategy for those making the decisions.