Illegal immigration booms and welfare in the host country

We assess the effects of an important influx of illegal immigration on production and welfare, applied to the Spanish economy during the nineties, through a calibrated general equilibrium model. Immigrants are perfect substitutes of unskilled native workers, according to their productivity, but they are unevenly rewarded. In a first simulation we analyse the effects of an exogenous increase of illegal workers equal to the estimates for the period. In another simulation an equivalent expansion in unskilled legal immigrants is then considered. Finally, a comparison of both simulations provides the scenario of illegal immigrants being legalised. The outcome suggests that the amount of remittances and the role of labour market mechanisms (e.g. trade unions) play an important role in overall results.