What would constitute a "competitive free market" for justice? It should first be understood that the mere presence of multiple justice providers would not be a sufficient condition to constitute such a market. (Multiple providers, incidentally, are not always present even in ordinary free markets, since natural monopolies may occasionally develop in the latter; cf. pp. 4.11:128 and 4.11:139.) A free market is a connected set of voluntary exchanges of two or more goods. From anarcho-capitalist writings, it is clear that the goods that are supposedly to be exchanged voluntarily are justice and money. (Strictly speaking, justice is not a single praxeological good, since its units are not homogeneous, but rather a collection of related goods.) Thus the anarcho-capitalist imagines, at least by implication, that justice would be bought and sold in a system of voluntary exchanges.

As we observed in our discussion of restitution, rational justice requires that the cost of justice be borne, not by the victims of injustice, but by its perpetrators (p. 5.5:65). In other words, the perpetrators would have to be the "buyers" in this alleged "market for justice." In a few cases, aggressors may indeed be willing to repay the costs of their aggression voluntarily, so that no use or threat of force would be required. In other cases, disputants might be able to settle their differences with the assistance of an arbitrator. In this respect the anarchist proposal resembles a system based on a limited liberal government, since these disputes could be resolved through voluntary private settlements under the latter system as well.