The economics of consanguineous marriages

The institution of consanguineous marriage-a marriage contracted between close biological relatives-has been a basic building block of many societies in different parts of the world. This paper argues that the practice of consanguinity is closely related to the practice of dowry, and that both arise in response to an agency problem between the families of a bride and a groom. When marriage contracts are incomplete, dowries transfer control rights to the party with the highest incentives to invest in a marriage. When these transactions are costly however, consanguinity can be a more appropriate response since it directly reduces the agency cost. The paper's model predicts that dowry transfers are less likely to be observed in consanguineous unions. It also emphasizes the effect of credit constraints on the relative prevalence of dowry payment and consanguinity. An empirical analysis using data from Bangladesh delivers robust results consistent with the predictions of the model.