Neither A Borrower Nor A Lender Be: An Economic Analysis of Interest Restrictions and Usury Laws
提出利率限制作为一种原始的社会保险机制，通过降低利率在收入边际效用高时向借款人转移收入，在低时向放贷人转移收入。模型预测不平等高、收入冲击大、增长低时限制更严，美国各州数据支持这一关联。
Interest‐rate restrictions are pervasive and important regulations. This article suggests that these restrictions served, in part, as a primitive means of social insurance. Lowering the rate of interest effectively transfers income to states of the world where individuals have a high marginal utility of income and are borrowers from states of the world where individuals have a low marginal utility of income and are lenders. The model predicts that interest‐rate restrictions will be tighter when income inequality is high and impermanent and when growth rates are low. Furthermore, loan supply must be somewhat inelastic. Data from U.S. states support a connection between inequality, income shocks, and tighter usury laws. Usury laws were also stricter in older, more stable communities. The history of usury laws suggests that this social insurance mechanism is one reason usury laws exist and persist, but this history also suggests that usury laws have played many roles across time and that no one theory can possibly capture all of these roles.