Despite the shrill political opposition to regularisation, it is far from unprecedented in Spain; PP and socialist governments enacted similar programmes between 1986 and 2005. Research suggests such initiatives can yield economic benefits for newly legalised workers and for government coffers.

Joan Monràs, one of the authors of a study into the 2005 regularisation of almost 600,000 non-EU immigrants, said tax revenues increased by about €4,000 per regularised immigrant a year, adding that the policy had not led to “magnet effects” in encouraging further arrivals.