Hence, there is no longer a need to defend its very existence. Legitimacy is procedural fairness. It expresses the preference for order and stability and the belief that for a system of rules to be fair, it must be firmly rooted in a framework of formal requirements about how rules are made, interpreted and applied. Distributive justice, on the other hand, is substantive fairness. It expresses the need for a justifiable distribution of costs and benefits, and usually favours change.
Distributive justice is rooted in the subjective, relative moral values of the community.
Legitimacy and justice may coincide, but they may also clash. The importance of fairness lies not only in its moral value, but also in the utilitarian aspect that it pulls towards voluntary compliance. In a situation of extreme scarcity, fairness would not be sought. Legitimacy is affected by properties of the rule, by the process by which it was made, and by its implementation. Textual determinacy is the ability of a text to convey a clear message.