This paper considers the use of outcomes-based tests for detecting racial bias in the context of police searches of motor vehicles. It shows that the test proposed in Knowles, Persico and Todd (2001) can also be applied in a more general environment where police officers are heterogenous in...

We consider an inspection game between $n$ polluting firms and an environmental enforcement agency. If the cost of monitoring ambient pollution is low enough, the optimal inspection policy consists in imposing the maximal possible fine, and mixing between observing ambient pollution and not...

This paper analyzes how enforcement along the U.S.-Mexican border has affected the market for migrant smugglers. Using a unique dataset that links border crossing histories from illegal Mexican migrants to aggregate enforcement and punishment statistics, we find that the effect of enforcement on...

The deterrent effect of law enforcement rests on the link between the actual and the perceived detection risk. We study the role of word of mouth for this linkage. Our approach makes use of micro data on compliance with TV license fees allowing us to distinguish between households who have been...

We show that the recent rise in Afghan opium production is caused by violent conflicts. Violence destroys roads and irrigation, crucial to alternative crops, and weakens local incentives to rebuild infrastructure and enforce law and order. Exploiting a unique data set, we show that Western...

We run a large-scale natural field experiment to evaluate alternative strategies to enforce compliance with the law. The experiment varies the text of mailings sent to potential evaders of TV license fees. We find a strong alert effect of mailings, leading to a substantial increase in...

The deterrent effect of law enforcement rests on the link between the actual and the perceived detection risk. We study the role of word of mouth for this linkage. Our approach makes use of micro data on compliance with TV license fees allowing us to distinguish between households who have been...

Broken Windows: the metaphor has changed New York and Los Angeles. Yet it is far from undisputed whether the broken windows policy was causal for reducing crime. In a series of lab experiments we show that first impressions are indeed causal for cooperativeness in three different institutional...

We discuss survey evidence on individuals' willingness to sanction norm violations such as evading taxes, drunk driving, fare dodging, or skiving off work by expressing disapproval or social exclusion. Our data suggest that people condition their sanctioning behavior on their belief about the...

We run a large-scale natural field experiment to evaluate alternative strategies to enforce compliance with the law. The experiment varies the text of mailings sent to potential evaders of TV license fees. We find a strong alert effect of mailings, leading to a substantial increase in...