Since we do not recognise dry rain, we would not choose to talk of "wet rain" when we mean rain. Embellishing it with "wet " would ring the alarm bell of logic telling us loudly and clearly that something has gone wrong. The exact nature of the wrong is made clearer in examples that are less obviously absurd. People talk solemnly of "impartial justice", as if "partial justice" were not a contradiction in terms. Treating it implicitly as a notion that is not non sensical permits the demagogue selectively to accept or reject outcomes of the judicial process to promote his political agenda. Wikipedia, the modern fountainhead of universal knowledge calls distributive justice the application of social justice; one wonders how it would define unsocial justice, and how social justice is supposed to be something other than distributive justice.
"Distributive justice" is equivalent in absurdity to "wet rain". All justice is distributive and cannot help it, any more than rain can help being wet. All justice, administrative, civil or criminal, distributes benefits or burdens in its judgments. The judgments, in turn, seek to comply with a system of rules that are conventions, common and statute laws, and judicial precedents. A system of liberties comprises all feasible acts that do not violate the rules of justice, so that justice and liberty correspond to the same definition. Titles to property of all kinds, including unexecuted contracts, are liberties of a particular kind. The rule of justice protects these liberties. For distributive justice to have any meaning of its own, it must be a sort of anti-justice overriding in a systematic manner the rule of justice, appropriating for itself jurisdiction over the special area of property, contract, and income. Unlike justice properly speaking, it has no rules. However, its decisions are not random or arbitrary for all that, for it claims uniform motives for them, as well as a legitimacy for them that is almost wholly different from the legitimacy of the rules of justice.
The rules of justice have sources that can be traced and identified. Convention results from the reciprocal accommodation of players to enhance payoffs. Law is made by legislators using a rule of rule-making which, in turn, is a product of collective choice, a.k.a. a constitution. Distributive justice has no such rules, but has a purpose or purposes which it is intended to achieve. The purposes, however, are at best debatable and elusive. To be told that distributive justice seeks to achieve social justice is not helpful. The reverse of this is no less futile. It resembles the wetting of water. Nor does it help to know that it seeks fairness in distribution - a statement that this is a barely disguised tautology. However, not all speculation about the why and the wherefore of distributive justice should be so easily waved away.
Since Jeremy Bentham injected it into social thought, utility has all but dominated it. Utility began its carrier as an intangible, invisible imaginary substance that affected the human mind. It did so carried by events and goods or their expectations. The mind feels pain and pleasure, happiness or wellbeing as a result. In the usual parlance, the carrier of utility to the individual was his income. The temptation was irresistible to conclude that the sum of utility must depend on how income was distributed between Peter and Paul. It could be augmented if some income was taken from rich Peter and given to poor Paul. It was further inferred that there must be a distribution of incomes at which the aggregate utility of society was at a maximum. By a further and rather cavalier assumption we owe mainly to Old Cambridge economists that this maximum was reached when nobody had a higher income than anybody else. Thus distributive justice had its clear purpose.
Two objections undermined this confortable stand. Since utility was just a mental construct almost anything could be alleged about it without fear of refutation. It was therefore attempted to determine its precise relation to income, its visible carrier. The Neumann-Morgenstern test did this by asking a person how much he would pay for a lottery ticket that offered an even chance between $100 and zero. If he would only pay less than $50, we could say that the utility of his income grew less than proportionately to the income. If he were willing to pay more than $50 his utility grew more than proportionately to the growth of his income. Here was a way to detect the shape of the utility function and in terms of cardinal and not merely ordinal terms, too.
Unfortunately the Neumann-Morgenstern test does not prove what it is generally supposed to do. The lottery ticket has a 50 per cent probability of wining if it is drawn infinitely many times, but the number of wins in a small number of draws is anybody's guess. It would be perfectly rational for the person put to the test to believe that his probability of winning in the next draw is either much lower or much higher than 50 per cent. We all know of notoriously lucky and cruelly unlucky people. If people do believe that they are usually unlucky or usually lucky, or that today is their lucky or unlucky day, they could therefore rationally pay more than $50 for the ticket. They could never the less pass for being both rational and having a utility function that could be said to be rising less steeply than their income. In fact almost anything could be imagined about it. The problem is that the Neumann-Morgenstern test seeks to discover two unknowns, utility and the subjective probability of an event, from one equation. As this cannot be done, the test is futile.
The other objection is more summary and lethal. In the 1930's economists rather belatedly understood that the utilities of different persons were not objectively commensurate (i.e. "can have no common measure") and could not be added to or subtracted from one another. In fact, we simply could not ever know anything at all about utility. Inserting it into consumer choice, risky choice, or welfare theory was a redundant and futile complication that could not add anything to knowledge.
The divorce of distributive justice from utility is still not neat and clear. Nostalgia still links them. Meanwhile, other claims have been added to make distributive justice rest on rational purpose. Perhaps the most popular is the claim that society is a big mutual insurance company protecting individuals from distress and unpredictable hazards. Distributive justice provides the insurance by taking premiums from some and paying off the claims of others. Everybody is satisfied.
In reality, the well-to-do would be silly to be satisfied. They could buy their own insurance, paying much lower premiums than would be the case if their premiums had to cover both their own risk and the risks of the needy. Distributive justice denies them this choice. The excess premiums they are made to pay represent redistribution from the well-to-do to the needy, a move towards equality. This is a rational purpose of distributive justice if, and to the extent that, moving towards equality is its rational purpose. For this to be accepted, equality must have intrinsic value, superior to inequality. This however, remains to be demonstrated, and assuming in our linguistic usage that it is the case is to beg the question.
When cave man became civilised, "might is right" was gradually restrained by the rule of justice, which was almost certainly a better evolutionary strategy for groups. Nearer our own age, two loopholes open up in the restraint, and are getting larger. Both are powerfully widened by the corruption of language.
As collective choice acquires the power to make rule-making rules that supplement or replace conventional rules, it typically excludes certain options and permits others. Thus, constitutions leave largely open to collective choice dispositions about taxation. The state is called upon to protect property against all comers except against itself. This is justified by the supremacy of the public interest over rules governing property. Public interest is supreme because no argument can long sustain the proposition that the interest of the public is not supreme. Thus, an elementary sleight-of-hand using a truism pierces and widens a loophole for distributive justice to rise above the rule of ordinary justice.
The other and equally convenient loophole is created by the persistent employment of the word "equal" as a moral qualification. Thus, "equal" comes to stand in relation to "unequal", and "equality" to "inequality", as "good" stands in relation to "bad", "true" to "untrue", "faithful" to "faithless" or "just" to "unjust". A more equal distribution of resources is eo ipso better than an unequal one, and no argument to the contrary could resist the charge of perversity or heartlessness. Distributive justice, by attempting to make the distribution of resources more equal, is serving justice.
It is the great good fortune of this somewhat shoddy doctrine that its demand coincides with what the modern form of collective choice, namely majority rule, produces, for majority rule is might disguised as right. By the same token, it is the great good fortune of democracy that its manner of awarding the control of government namely redistribution, happens to coincide with what distributive justice, a doctrine of moral superiority, demands of it. "Might is right" is back with a vengeance.