This article introduces ParliamentLab.eu, an interactive application paired with a structured dataset, designed to support the exploration of voting behavior in the European Parliament (EP) from 2004 to 2022. ParliamentLab integrates publicly accessible datasets from VoteWatch.eu and Parltrack.eu, containing roll-call votes, biographical details, and attendance records into one intuitive interface. The application enables users to interactively filter data, visualize voting patterns, and perform hypothesis-driven exploration without requiring programming expertise. The user-adapted data can be downloaded as well. In its current form, ParliamentLab includes advanced techniques such as clustering and dimensionality reduction, modestly featuring a clustering process to show how underlying data structures can be identified. This feature supports interactive data exploration while keeping the focus on low-barrier accessibility. ParliamentLab provides researchers, educators, journalists, and the public with a transparent, reproducible, and user-friendly tool for engaging with legislative behavior in the EP.

Vague legislative language can facilitate law adoption and implementation but reduce policy effectiveness and application uniformity. So, when do legislators employ it? Building on policymaking and responsiveness theories, we argue that legislators use vague language to overcome institutional conflict and public opinion constraints but avoid it when they seek to assert their positions in legislative output and policy outcomes. Empirically, we study the conditions under which the European Parliament (EP) introduces vague amendments to European Union (EU) legislative proposals using dictionary-based content analysis of EU legislative negotiations between 2009 and 2019. The results show that EP sticks to more concrete positions when inter-institutional conflict threatens its policy goals but employs vagueness to maintain a broad appeal and avoid public backlash given public opinion divisions and contentiousness. These results add to our knowledge of legal text formulation, EU law making, and EP representation.

This article seeks to explore the nature and determinants of political conflict in European Parliament (EP) debates within the unique context of the Rule of Law Crisis (RoLC). While previous research on this topic has mainly studied the ideological dimension of this conflict, we shift focus to the affective dimension, analysing the roles of negative sentiment and motive-based criticism through a quantitative analysis of 53 hand-coded debates. We find that negativity dominates, and that this tone is adopted by Members of the EP (MEPs) irrespective of the ideological orientation or geographical origin of their national party. However, concerning levels of motive-based cynicism are primarily driven by MEPs from more right-wing, Eurosceptic and, to a lesser extent, Central and Eastern European parties. These findings suggest that the EP, an institution traditionally geared towards compromise-building, is becoming increasingly susceptible to the normative jeopardies of negative and attack politics when it comes to the RoLC.

This research note presents BLUE_EP, the first dataset of municipality-level results of European Parliament (EP) elections. Our dataset covers the 2019 and 2024 EP elections and provides results for approximately 90,000 Local Administrative Units (LAUs) in the EU27 and 500 parties or lists in each election, along with a classification of all parties into political groups and broader political families. The dataset was constructed by collecting, harmonizing, and merging 27 national datasets, closely following the standard European and national GIS typologies for LAUs. To the best of our knowledge, BLUE_EP is the first dataset to support a uniform, Europe-wide analysis of local voting behavior in EP elections. To showcase the usefulness of our dataset, we combine BLUE_EP with European Commission data on population demographics and degrees of urbanization. Using the combined datasets, we provide fine-grained evidence for a widening urban-rural gap in voting behavior between the 2019 and 2024 EP elections.

European elections consistently show lower turnout compared to national elections. Two types of explanations have been proposed. The first is the “don’t know” explanation: European citizens are not adequately informed about what the EU does, what the role of the European Parliament (EP) is, and what impact their vote can have. The second explanation is that they “don’t care”: voters do not care about European elections because they might think that EU policies do not affect them or that the European Parliament is not an important actor in EU politics. I use a between-subject survey experiment in 16 EU countries, with approximately 30,000 respondents, one month before the 2024 European elections, with a follow-up in the days after the vote, to see whether giving voters more information about what the European Parliament does and presenting respondents with hypothetical increases in the powers of the European Parliament, affects their intention to vote and eventual real-world vote. Results show that information increases likelihood to vote. Importantly, these effects last and increase actual voting propensity a month later. Surprisingly, hypothetical increases in the powers of the EP decrease the likelihood to vote among almost all groups of respondents. Among respondents that are skeptical of the EU or perceive a democratic deficit, this negative effect is more pronounced. Even among pro-EU respondents and among those that prefer to see a stronger role for the Commission, the backlash is strong. When considering increasing the powers of the EP, the European Union has little to gain and much to lose when it comes to civic participation. The EU needs to first improve its legitimacy before considering political reforms.

This Article contributes toward the growing body of literature addressing the burgeoning gap between normative and empirical accounts of constitutional change in the constitutional order of the European Union. It does so by shining a light on how the European Parliament, acting through its unilateral procedural rule making powers, has managed to wield its limited formal constitutional clout to alter the balance of powers between the core Union institutions, and to define its own role in the development of the political component to the EU’s constitutional culture. Given the European Parliament cannot be dissolved, and given there is at least the potential for such rule making power to be put to unconstitutional ends, the Article also considers the extent to which judicial oversight of this particular form of informal constitutional change is possible, and the form it may take should the validity of a particular procedural rule be challenged.

Multiple rounds of European Union (EU) enlargement and the rise of the populist radical right have affected the organisation of political competition in the European Parliament (EP). This study probes how the EU’s efforts to redress democratic backsliding in several EU member states crystallise deepening divides between European lawmakers. Our empirical analysis examines 17 roll-call votes on rule of law issues and well over 900 discursive statements from corresponding parliamentary debates held between 2009 and 2019. Our unique approach enables us to analyse discursive and voting patterns both separately and jointly to understand how they affect each other. We find that behaviour across these different arenas is generally consistent and aligns with an ideological divide that pits Eurosceptic Members of the European Parliament (MEPs) against representatives from pro-EU European party groups. Once we account for ideological orientations and strategic motivations, the often-claimed East–West divide on rule of law issues becomes much less salient, emerging primarily under specific conditions of ongoing democratic erosion and national incumbency in Central and Eastern Europe. Our findings speak to the literature on EU responses to democratic backsliding as well as to the changing dynamics of political competition in the EU more broadly.

This paper is in line with research that analyzes the careers of European parliamentarians, adopting a comparative and cross-sectional approach and taking into account previous and subsequent political experiences in a multilevel perspective. Indeed, we propose a comparison between two similar cases, namely two southern European countries that have a quasi-federal system or are affected by an important regionalization process – Spain and Italy – and we examine a rather long time period ranging from the IV to the IX EP legislature. Our dataset consists of 508 observations, 195 relating to Spanish members of the European Parliament (MEPs) and 313 to Italian ones. By relying on the recent systematization, we propose to classify MEPs’ career models – which are our dependent variable – into four types: the EU shorter-termers, the ‘stepping stone’ MEPs, the EU long-termers, and the ‘multilevel surfers’. A multinominal regression analysis was conducted to understand which political factors (party affiliation of MEPs, length of previous career, critical European Parliament [EP] elections) may have a specific impact on each career type. We found that, after the 2014 EP critical election, the probability of MEPs engaging in the EP decreases, as they are more likely to develop a short-term career model than a long-term one. In addition, previous national experience and a regional executive career are the best predictors of a multilevel career.

Drawing on an original dataset covering more than 100 political parties in over 20 European Union Member States, this article analyses how political recruitment procedures affect the proportion of women nominated on party lists in the context of the 2009 European Parliament elections. The findings show that the inclusiveness of the selectorates in the early stage of candidate selection processes is a key determinant of the representativeness of lists regarding their gender composition. Moreover, it is found that neither territorial centralisation nor the inclusiveness of the selectorate in the later stage of candidate selection play a significant role. The key to the puzzle, therefore, lies in the composition of the initial pool of potential candidates and those who make initial nominations.

In many political systems, legislators serve multiple principals who compete for their loyalty in legislative votes. This article explores the political conditions under which legislators choose between their competing principals in multilevel systems, with a focus on how election proximity shapes legislative behaviour across democratic arenas. Empirically, the effect of electoral cycles on national party delegations’ ‘collective disloyalty’ with their political groups in the European Parliament (EP) is analysed. It is argued that election proximity changes the time horizons, political incentives and risk perceptions of both delegations and their principals, ‘punctuating’ cost‐benefit calculations around defection as well as around controlling, sanctioning and accommodating. Under the shadow of elections, national delegations’ collective disloyalty with their transnational groups should, therefore, increase. Using a new dataset with roll‐call votes cast under legislative codecision by delegations between July 1999 and July 2014, the article shows that the proximity of planned national and European elections drives up disloyalty in the EP, particularly by delegations from member states with party‐centred electoral rules. The results also support a ‘politicisation’ effect: overall, delegations become more loyal over time, but the impact of election proximity as a driver of disloyalty is strongest in the latest parliament analysed (i.e., 2009–2014). Furthermore, disloyalty is more likely in votes on contested and salient legislation, and under conditions of Euroscepticism; by contrast, disloyalty is less likely in votes on codification files, when a delegation holds the rapporteurship and when the national party participates in government. The analysis sheds new light on electoral politics as a determinant of legislative choice under competing principals, and on the conditions under which politics ‘travels’ across democratic arenas in the European Union's multilevel polity.

Can a directly elected European Parliament help deliver standards by which the European Union can be indirectly legitimated through its component national democracies? This article argues that the Union can be indirectly legitimate where it helps member state democracies meet their own obligations to their own publics. The Union can do just that by managing externalities in ways needed to secure core values of justice, democracy and freedom from arbitrary domination within member states. Yet that poses a predicament: for if any one member state has an interest in imposing negative externalities or in freeriding on positive externalities provided by another, then so may its voters and democratic institutions. The article argues a directly elected European Parliament can help manage that predicament both by identifying externalities and by ensuring their regulation meets standards of public control, political equality and justification owed to individual national democracies.

Voters behave differently in European Parliament (EP) elections compared to national elections because less is at stake in these ‘second‐order’ elections. While this explains the primary characteristic of EP elections, it has often led to a conflation of distinct motivations for changing behaviour – namely sincere and protest voting. By distinguishing these motivations, this article addresses the question of when and why voters alter their behaviour in EP elections. In addition, it argues that the degree of politicisation of the EU in the domestic debate shapes the extent to which voters rely on EU, rather than national, considerations. These propositions are tested in a multilevel analysis in 27 countries in the 2009 EP elections. The findings have important implications for understanding why voters change their behaviour between different types of elections.

Citizens' ability to hold corrupt politicians accountable is a key feature of democratic political systems. Particularly in the European Union (EU), such accountability mechanisms are often argued to malfunction due to the EU's complicated and opaque institutional structure, which could compromise voters' basic abilities to detect political malpractice in Brussels. Putting EU voters' attentiveness to the test, we provide quasi‐experimental evidence of the causal effect of a recent corruption scandal in the European Parliament. Leveraging an ‘Unexpected Event during Survey Design’ identification strategy in France and Germany, we document a sizeable negative effect of the so‐called Qatargate scandal on public trust in the European Parliament. This provides causal evidence on the presence of attentiveness to EU politics within these electorates. Given the EU's complex institutional structure, we derive two alternative implications from this finding.

The 2014 European Parliament (EP) elections produced a record proportion of women MEPs overall (37 per cent). Yet, these results vary widely across countries and parties. This article aims to explain these variations, evaluating not only who the elected representatives of the 8th EP are, but also how they got there. Are the paths to the EP the same for women and men? Are there gender differences in terms of MEPs’ political experience? A unique dataset listing more than 700 elected MEPs and their background, party and country characteristics is used to empirically examine who makes it to the EP and through which route. The results of the analysis suggest no significant gender differences in the pathways to the EP. Yet, parties matter: more women were elected to the 8th EP from left‐wing than from right‐wing or ‘new’ parties, and both men and (especially) women representing right‐wing parties tend to be politically more experienced than their fellow MEPs from other types of parties. Furthermore, it is found that men are more likely than women to be promoted straight from party office to the EP, suggesting that some pathways to the EP are less open to women than others.

The 2014–2019 European Parliament (EP) contained an unprecedented number of Eurosceptic Members of the European Parliament (MEPs). These changes reflected a growing politicisation of European integration in which conflicts between those opposing the process and those favouring it became more pronounced. Using a unique time series of surveys of the European parliamentarians, we examine how far the policy preferences of the MEPs responded to this politicisation. MEPs' preferences over general policy questions as well as European Union (EU)‐specific issues have traditionally been described by a multi‐dimensional space: with a left‐right dimension, incorporating both economic and socio‐cultural issues, distinct from a pro‐/anti‐Europe dimension. We find that the political space in the EP evolved in the 2014–2019 parliament, with MEPs' preferences more strongly aligned along a single dimension, which captures economic, socio‐cultural, and EU integration issues.

The 2008/2009 economic crisis has been identified as an important element contributing to declining trust in institutions in Europe and worldwide. However, it is unclear whether this decline in trust is distributed homogenously among citizens or whether there are differences across social strata. This article applies multilevel models to six waves of European Social Survey (ESS) data to analyse changes in trust in the European Parliament (EP) from 2002 to 2012 in 20 European Union countries. Moreover, it investigates whether individuals with different socioeconomic backgrounds experienced different reductions in trust. The results indicate that trust in the EP declined the most in the peripheral European countries hit hardest by the economic crisis: Portugal, Italy, Ireland, Cyprus, Greece and Spain. Furthermore, the results suggest that the decline in trust was more pronounced among subjects with lower social status. The tightening of the link between social and political inequalities is especially preoccupying considering the importance of trust in institutions for citizens to actively participate in society, voice their needs and demand their place at the table. Hence, the worsening economic conditions, combined with declining levels of trust, are not only troublesome for the functioning of democracies as a whole, but they are also problematic at the individual level as they are likely to perpetuate the divide among subjects at different ends of the social ladder.