“Give Them a Hand They Will Take the Whole Arm”?

Co-author: Emanuel Massetti, University of Edinburgh This paper aims to investigate: 1) whether decentralization tends to favour autonomist or secessionist ethno-regionalist parties; and 2) whether ethno-regionalist parties tend to radicalise or moderate their self-government claims as a consequence of decentralization. It distinguishes between a level effect (absolute level of decentralization in the region) and a process effect (change in the level of decentralization); and between their impact in regional and national elections. This study employs several datasets: 1) the regional authority index (RAI) dataset is used to measure the level of (and the change in) decentralization; 2) a novel dataset which codifies 77 regionalist parties’ self-government claims in a 1 to 6 scale is used to measure radicalism; 3) and a novel dataset which includes vote shares for these parties in regional and/or national elections from 1950 until 2010 is used for election data. Our findings show that decentralization reforms tend penalise moderate ethno-regionalist parties more than radical ones in national elections. However, we also find that decentralization reforms tend to reward moderate ethno-regionalist more than radical ones in regional elections. The paper provides explanations for these trends and investigates their relative impact on ethno-regionalist parties’ ideological adaptation.