While there is ample evidence that the possibility to hold dual citizenship is a key predictor of the propensity to naturalise among immigrants, existing research on the causal and heterogenous effects of policy reforms is limited. In this paper we analyse the effect of contrasting policy reforms in two West European migration destinations: a restrictive change in the Netherlands (1997) and a liberalising change in Sweden (2001). We apply a difference-in-differences design and identify the treatment effect of destination country policy reform based on origin country citizenship legislation data around the world. Our analyses employ microlevel administrative register data on migration populations in the years around these reforms. We find that the effect of dual citizenship acceptance is concentrated among immigrants from EU and other highly developed countries. Our findings add quasi-experimental evidence to studies on the relevance of dual citizenship acceptance for immigrant naturalisation and inform public debates about the impact of citizenship law reform.
Speaker: Maarten Peter Vink (EUI – R.Schuman Center)