BBC
Illegal Immigration: Is an amnesty the answer?
…Researchers at the Centre on Migration, Policy and Society at the University of Oxford have looked at previous studies, in particular ones of a United States amnesty in 1986. — They found that “almost all show that the large-scale amnesty implemented in 1986 has not reduced, and has in fact increased, [illegal immigration] to the US, since it established new migration flows due to networks and family ties.”
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