This article introduces the Twitter Parliamentarian Database (TPD), a multi-source and manually validated database of parliamentarians on Twitter. The TPD includes parliamentarians from all European Free Trade Association countries where over 45% of parliamentarians are on Twitter as well as a selection of English-speaking countries. The database is designed to move beyond the one-off nature of most Twitter-based research and in the direction of systematic and rigorous comparative and transnational analysis. The TPD incorporates, in addition to data collected through Twitter’s streaming API and governmental websites, data from the Manifesto Project Database; the Electoral System Design Database; the ParlGov database; and the Chapel Hill Expert Survey. By compiling these different data sources it becomes possible to compare different countries, political parties, political party families, and different kinds of democracies. To illustrate the opportunities for comparative and transnational analysis that the TPD opens up, we ask: What are the differences between countries in parliamentarian Twitter interactions? How do political parties differ in their use of hashtags and what is their common ground? What is the structure of interaction between parliamentarians in the transnational debate? Alongside some interesting similarities, we find striking cross-party and particularly cross-national differences in how parliamentarians engage in politics on the social media platform.

Ideas about morality are deeply entrenched into political opinions. This article examines the online communication of British parliamentarians from May 2017-December 2019, following the 2016 referendum that resulted in Britain's exit (Brexit) from the European Union. It aims to uncover how British parliamentarians use moral foundations to discuss the Brexit withdrawal agreement on Twitter, using Moral Foundations Theory as a classification basis for their tweets. It is found that the majority of Brexit related tweets contain elements of moral reasoning, especially relating to the foundations of Authority and Loyalty. There are common underlying foundations between parties, but parties express opposing viewpoints within a single foundation. The study provides useful insights into Twitter’s use as an arena for moral argumentation, as well as uncovers the politician’s uses of moral arguments during Brexit agreement negotiations on Twitter. It contributes to the limited body of work focusing on the moral arguments made by politicians through Twitter.

The question of the democratic character of the European Union (EU) has been a center-point of decades of political research. An important critique suggests that the development of the European political arena is still incomplete, with European parliamentarians primarily orienting themselves to national issues and politicians, implying a problematic mismatch between the political arena and their policy jurisdiction. Research has however been limited by methodological difficulties of capturing the level of Europeanization of the political arena. This paper contributes a novel method for measuring Europeanization by studying interactions from the European parliament to their national parliamentarians on Twitter in 15 EU countries. Contrary to expectations in the literature, we find substantial Europeanization of the political arena. The level of Europeanization furthermore varies greatly across countries and political groups. This has important implications on the debate on EU’s democratic deficit, as communication across different levels of parliament indicates democratic debate.