This paper develops a model of the interaction between the supply of hate-creating stories from politicians and the willingness of voters to listen to hatred. Hatred is fostered with stories of an out-group's crimes, but the impact of these stories comes from repetition not truth. Hate-creating stories are supplied by politicians when such actions help to discredit opponents whose policies benefit an out-group. Egalitarians foment hatred against rich minorities; opponents of re-distribution build hatred against poor minorities. Hatred relies on people accepting, rather than investigating, hate-creating stories. Hatred declines when there is private incentive to learn the truth. Increased economic interactions with a minority group may provide that incentive. This framework is used to illuminate the evolution of anti-Black hatred in the United States South, episodes of anti-Semitism in Europe, and the recent surge of anti-Americanism in the Arab world.

A central requirement in the design of a legal system is the protection of law enforcers from coercion by litigants through either violence or bribes. The higher the risk of coercion, the greater the need for protection and control of law enforcers by the state. Such control, however, also makes law enforcers beholden to the state, and politicizes justice. This perspective explains why, starting in the twelfth and thirteenth centuries, the relatively more peaceful England developed trials by independent juries, while the less peaceful France relied on state-employed judges to resolve disputes. It may also explain many differences between common and civil law traditions with respect to both the structure of legal systems and the observed social and economic outcomes.

If economic growth relies upon the extent-of-the-market, then openness will decrease the connection between initial income and later growth. Alternatively, learning-by-doing models suggest that wealth will be more positively correlated with growth in open economies, because trade causes advanced economies to specialize in products with more opportunities for learning. We examine twentieth century less developed countries and nineteenth century U. S. states. In both data sets, there is a much stronger correlation between growth and initial wealth among closed economies. These findings support the importance of the extent-of-the-market, and aggregate demand in fostering growth.

Using theory, case studies, and cross-country evidence, we investigate the factors behind the concentration of a nation's urban population in a single city. High tariffs, high costs of internal trade, and low levels of international trade increase the degree of concentration. Even more clearly, politics (such as the degree of instability) determines urban primacy. Dictatorships have central cities that are, on average, 50 percent larger than their democratic counterparts. Using information about the timing of city growth, and a series of instruments, we conclude that the predominant causality is from political factors to urban concentration, not from concentration to political change.

Spatial separation of racial and ethnic groups may theoretically have positive or negative effects on the economic performance of those groups. We examine the effects of segregation on outcomes for blacks in schooling, employment, and single parenthood. We find that blacks in more segregated areas have significantly worse outcomes than blacks in less segregated areas. We control for the endogeneity of location choice using instruments based on political factors, topographical features, and residence before adulthood. A one standard deviation decrease in segregation would eliminate one-third of the black-white differences in most of our outcomes.

The high variance of crime rates across time and space is one of the oldest puzzles in the social sciences; this variance appears too high to be explained by changes in the exogenous costs and benefits of crime. We present a model where social interactions create enough covariance across individuals to explain the high cross-city variance of crime rates. This model provides an index of social interac-tions which suggests that the amount of social interactions is highest in petty crimes, moderate in more serious crimes, and almost negligible in murder and rape. Quelquefois aussi le crime prend sa source dans l'esprit d'imitation, que l'homme possede 'a un haut degre et qu'il manifeste en toutes choses [A. Quetelet 1835]. I.

Party platforms differ sharply from one another, especially on issues with religious content, such as abortion or gay marriage. Given the high return to attracting the median voter, why do vote-maximizing politicians take extreme positions? In this paper we find that strategic extremism depends on an intensive margin where politicians want to induce their core constituents to vote (or make donations) and the ability to target political messages toward those core constituents. Our model predicts that the political relevance of religious issues is highest when around one-half of the voting population attends church regularly. Using data from across the world and within the United States, we indeed find a nonmonotonic relationship between religious extremism and religious attendance.