An important class of active labor market policy has received little impact evaluation: immigration barriers intended to raise wages and employment by shrinking labor supply. Theories of endogenous technical advance raise the possibility of limited or even perverse impact. We study a natural policy experiment: the exclusion of almost half a million Mexican 'bracero' farm workers from the United States to improve farm labor market conditions. With novel archival data we measure state-level exposure to exclusion, and model the labor-market effect in the absence of technical change. We reject such an effect and fail to reject a null effect.
Keywords: F22; J08; J38; J61; barrier; bracero; displace; employment; farm; foreign; immigrant; immigration; labor; mexico; native; restriction; visa; wages; worker.