Border enforcement of immigration laws attempts to raise the costs of illegal immigration, while interior enforcement also lowers the benefits. Border and interior enforcement therefore reduce the net benefits of illegal immigration and should lower the probability that an individual will decide to migrate. While some empirical studies find that border and interior enforcement serve as significant deterrents to illegal immigration, immigration enforcement is costly and carries significant unintended consequences, such as an increase in fraudulent and falsified documents and rising border death rates as migrants undertake more dangerous crossings.
Border enforcement works as intended: it drives up the cost and risks associated with border crossings and deters illegal immigration.
Border enforcement results in more positively selected migrant flows, possibly due to the higher costs of crossing.
Preliminary evidence suggests that interior enforcement lowers the net benefits of migration, which should act as a deterrent.
While the cost of enforcement is a burden on taxpayers, native workers may benefit when there is less competition from migrants entering.
The unintended consequences of border and interior enforcement are reduced when accompanied by other immigration reforms, such as a regularization program.
Intensified border enforcement leads to reduced circular migration, higher demand for smugglers, riskier crossings, and more migrant deaths.
Using border enforcement to keep migrants out causes wages to rise in the destination country and fall in the source country, changes which counteract the higher crossing costs and can increase the incentives to migrate.
Employer verification mandates correlate with lower employment and wages among unauthorized immigrants.
Additional interior enforcement can increase informal sector employment, where workers and employers evade taxation and regulation.
Immigration enforcement is costly and can divert resources from other federal and state law enforcement.