The previous chapter has described the economic rationale underlying some peculiarities of marriage law. It explained that the non-enforcement of some marital promises and basic legal remedies lower the costs of the administration of justice. However, the legal regulation of marriage goes beyond those features, as the law contains other – optional and imperative – rules for the spouses. If we assume that marriage is a contract – a tool to encourage the realization of investments in order to generate mutual benefits – it is necessary to demonstrate that the legal provisions in marriage law actually respond to this logic. The following pages are focused on providing a conceptual framework that explores in a comprehensive manner the economic rationale behind mandatory and default rules. Although it is undeniable that culture, belief, religion and other local features influence law-making, marriage law – as it has developed in a number of modern national laws – can be understood as a coherent system of incentives that induce cooperation between spouses in the same way as contract law does with contractual parties. The chapter is divided into two sections. In the first one, the cases that justify the imposition of restrictions on the freedom of choice are discussed. The second deals with the nature of default rules and their importance in the context of marriage.

RULES OF OBLIGATORY COMPLIANCE FOR THE SPOUSES

From an economic point of view, allowing individuals to decide freely with whom to contract and permitting them to define the conditions that govern these relationships is very welcome. This freedom would contribute to maximizing the benefits from their transactions, and accelerate the allocation of resources to those that value them at most. However, not all transactions lead to an improvement, as some arrangements can generate damage, injuries or other costs to contractual or external parties. A system based on the free exchange of goods and services can certainly fail. If that is the case, the imposition of limits on party autonomy is unavoidable to assure an efficient allocation of resources. It is here where provisions of obligatory compliance come into play.