This paper assesses the relationship between trade unions, equality-enhancing institutions (welfare states and collective bargaining) and the restrictiveness of labour migration policy in European countries between 1980 and 2010. We understand immigration policy and welfare protection as two alternative strategies pursued by trade unions to protect their core members against the risk of low-wage competition by migrants: restrictive immigration policy limits the labour supply and fosters wage progression, while welfare protection and solidaristic collective bargaining reduces the ability of employers to take advantage of immigrants’ lower reservation wages. We argue that weaker trade unions that are unable to equalise the labour market through welfare expansion will push for more restrictive immigration policies. In contrast, unions that are able to establish solidaristic institutions in the labour market can “afford” more open labour migration policies. We test these propositions by means of time-series cross-sectional regressions and short case studies of Germany and Sweden.
