The Rule of One-Third

The Rule of One-Third guaranteed wives a life interest in one-third of their husband's estate upon marital dissolution. We document the ubiquity of this legal construct and demonstrate that children's outcomes are imperiled absent a wife's residual claim on her husband's estate. Using ancient Roman law as an example, we argue that the patriarch, or paterfamilias, is the primary legal entity with an interest in creating and enforcing the Rule of One-Third. In a game-theoretic model, we show that the Rule of One-Third obtains when mothers and fathers are equally important in producing children's human capital and when it is enforced by the paterfamilias or by modern legal institutions. The Rule of One-Third places the cost of marital dissolution on the household rather than society and solves a contracting problem between the husband and wife when each is specialized in tasks the other cannot perform well. Copyright 2002 by the University of Chicago.