Do the regional and European content of legislation shape party behavior in national parliaments? an analysis of the Spanish case

Using the Spanish case, this paper explores whether the European and regional content of legislation debated in national parliaments influences parties’ legislative behaviour, and more specifically their decision to propose legislative amendments. Based on regression analysis and multilevel modelling for hypothesis testing and an original dataset including information on more than 90,000 amendments, results illustrate that parties are more likely to propose amendments on bills having regional content. This is explained because self-government between the state and regional authorities remains open to renegotiation and due to the persistent territorial cleavage. Yet, against the niche party literature, results show that both regional and statewide parties propose a significant number of amendments on bills having regional content, especially when territorial affairs are politicised. Regarding the European dimension, despite the absence of hard Eurosceptic parties in Spain and the lack of a strong political cleavage over European integration, our findings challenge the idea that in Europhile countries EU-related bills are rarely amended. Overall, while previous literature has primarily focused on governmental factors to explain parties’ decisions to propose amendments on national legislation, this paper highlights the importance of considering multi-level dynamics.