Who polarizes parliament? Partisan hostility in Norwegian legislative debates

In many democratic societies, research has identified an increase in animosity between supporters of different political parties. While this phenomenon has been extensively examined among the general public, less research has explored the role of political elites in contributing to partisan hostility. This study aims to fill this research gap by analyzing instances where members of parliament (MPs) express negative sentiments toward representatives of opposing parties in legislative speeches. Specifically, we investigate which MPs within parties are driving elite rhetorical polarization. We hypothesize that MPs with less experience in parliament and less experience outside of party politics are more likely to contribute to polarizing speech due to stronger partisan identities. Analyzing Norwegian MPs’ speeches between 1998 and 2016, we find support for these hypotheses. Our findings highlight intra-party differences in polarization and contribute new insights into the characteristics that shape polarizing rhetoric among political elites.