From illegal drugs, stolen artwork, and forged trademarks, to fraud in financial markets - the phenomenon of illegality in market exchanges is pervasive. Illegal markets have great economic significance, have relevant social and political consequences, and shape economic and political...

Legal and illegal markets often coexist. In theory, marginal legalization can either substitute for the remaining parallel market, or complement it via scale effects. I study migrants crossing without prior authorization at the US southwest border, where large-scale unlawful crossing coexists...