JCMS 2022 pp. 1–18 DOI: 10.1111/jcms.13371 Legislative Transparency in the European Parliament: Disclosing Legislators’ Meetings with Interest Groups NURIA FONT and IXCHEL PÉREZ-DURÁN Universitat Autònoma de Barcelona, Barcelona Abstract Research on transparency in the EU and at the European Parliament, in particular, has extensively examined the adoption and implementation of transparency initiatives as well as the conditions un- der which interest groups have access to and influence on EU policy-making. However, the ques- tion of whether Members of the European Parliament (MEPs) are transparent regarding their inter- actions with interest group representatives has been overlooked by the literature. This study addresses the question of the conditions under which MEPs are more likely to provide information about their meetings with interest groups. The study engages with institutional theory by empha- sizing that formal and informal rules incentivize MEPs’ behaviour. Drawing on a dataset on MEPs’ reports on their meetings with interest group representatives, the study demonstrates that proce- dural rules, party’s position on the cultural dimension and the national corruption tradition affect legislators’ propensity to disclose information about their meetings with interest groups. Keywords: European Parliament; members of the European Parliament; transparency; interest groups Introduction Over recent decades, several transparency initiatives have been launched by the European Parliament (EP) and in general at the European Union (EU) level with the aim of improv- ing the democratic accountability of decision-making. One of the main concerns has been regulating interest groups’ access to EU policy-makers. Parallel and in relation to these institutional endeavours, two bodies of literature have addressed related issues. On the one hand, research on interest groups at the EP has investigated the nature of the interactions between interest groups and legislators, and the conditions under which these interactions occur. Recent contributions focus on the EU lobbying regulation regime (Bunea, 2018, 2019), organized interests’ density (Carroll and Rasmussen, 2017), groups’ access to the EP deliberative process (Coen and Katsaitis, 2019) and influence on policy outcomes (Klüver et al., 2015; Kurtzer and Cooper, 2013; Marshall, 2010; Rasmussen, 2015), MEPs’ recognition of interest groups (Ibenskas and Bunea, 2020), and the transparency of business lobbyists in the EU (Naurin, 2007). On the other hand, recent research on transparency at the EP has focused mostly on trilogues and informal policy-making (for example Brandsma, 2019; Curtin and Leino, 2017) and on interinstitutional negotiations (Broniecki, 2019). All these studies provide valuable empirical evidence and theoretical insights into groups’ access, influence and recognition, as well as the disclosure of information about legislative bargaining. However, to the best of our knowledge, the question of MEPs’ transparency on their contacts with organized representatives has not been addressed in the specialized literature. This study aims to fill this gap by addressing the following © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. 2 Nuria Font and Ixchel Pérez-Durán research question: Under what conditions are MEPs more likely to report on their meetings with representatives of interest groups? The study engages with institutional theory by assuming that certain formal and informal rules incentivize and constrain political behaviour (North, 1990). In the identification of rules affecting transparent behaviour, we borrow arguments from the literature on government accountability and transparency, and contextualize them in the study of legislators’ incentives and behaviour in the EP. In particular, we examine how transparent behaviour in the EP is affected by parliamentary procedures as formal rules, the party’s position on the cultural dimension and its populist stance reflecting collective beliefs and ideas, and national traditions in regard to corruption as unwritten norms internalized by societies. The normative implications of legislative and government transparency have been widely discussed in the literature with inconclusive results. Critics argue that transparency in open-door bargaining may increase politicians’ incentives to posture and, thereby, lead to undesirable outcomes (Stasavage, 2004), and that transparency does not necessarily increase legislators’ responsiveness to voters in non-democratic countries (Malesky et al., 2012). In the EU context, some studies indicate that high levels of transparency may reduce the quality of deliberation and policy outcomes (Lindstedt and Naurin, 2007). In contrast, transparency is often seen as an instrument to increase legislators’ responsiveness to their voters (Carey, 2009), as a prerequisite of good governance (Heald, 2006), and as a tool to enhance democratic accountability (Lassen, 2005). As for the transparency of legislators’ contacts with interest groups, openness in decision-making is frequently perceived as fairer than procedures that take place behind closed doors (De Fine Licht et al., 2014). Turning to the EU, transparency is commonly seen as a practice that contributes to the dispelling of suspicion of legislative capture (Rasmussen, 2015) and emphasizes the ‘input-oriented goals of democratic legitimation’ (Héritier, 2003). Based on data on MEPs’ reports on their meetings with interest representatives during the first two years of the ninth legislature, our findings show that legislative transparency in the EP is more likely to occur when legislators, because of the policy position they hold, are required to report on their meetings with interest representatives; when they are members of parties with libertarian positions; and when they come from countries with stronger corruption-mitigation regimes. The study contributes to research on legislative transparency by providing arguments on how different types of formal and informal rules affect legislators’ decision to inform on their interactions with interest representatives. The paper is organized as follows. The next section addresses the notion of transparency in the EU legislative process. Following that, our theoretical expectations are elaborated. The subsequent sections describe the data and operationalization and the results of the analysis. The final section presents the main conclusions and discusses the implications of the study. I. Transparency in the EU Legislative Processes Transparency is commonly seen as a prerequisite for democratic accountability as it provides citizens with information about their representatives’ activities (Kleine, 2018). Scholars who focus on transparency emphasize the idea that transparency is a relational © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. Legislative transparency in the European Parliament 3 action in which different types of information providers and information recipients participate (Meijer, 2013). In this respect, transparency commonly refers to enabling the public to access information about how a given organization is structured and how it operates. Based on previous work by Heald (2006) and Grimmelikhuijsen and Welch (2012), three dimensions of government transparency can be identified: transparency on decision-making, on policy content, and on policy outcomes. While the first refers to the disclosure of information about decision-making processes to the public, the second and third focus on information about aspects related to the substance of policies. By focusing on how decisions are made, transparency of decision-making is particularly relevant as it refers to the degree of openness related to the steps taken to reach a decision and the rationale behind such decision (Grimmelikhuijsen and Welch, 2012). Transparency in decision-making in the legislative arena may cover, for instance, information on legislative bargaining, on committee and plenary voting results, and on policy-makers’ interactions with interest groups. Our study shares the conceptualization of transparency as a relational activity and analyses MEPs’ publications of their meetings with interest groups. By doing so, our notion of transparency is focused on decision-making. In the EU context, several transparency initiatives have been adopted with the purpose of regulating the involvement of private actors in decision-making processes (Bunea, 2018). Regarding the case of the EP, the most-outstanding initiatives include the creation and successive reforms of the Transparency Register and, more specifically, the establishment of transparency requirements in the EP Rules of Procedure (RoP). According to the RoP, MEPs should meet with only those interest-group representatives who have been registered in the Transparency Register (RoP 11.2). Moreover, RoP 11.3 establishes that ‘Members should publish online all scheduled meetings with interest representatives falling under the scope of the Transparency Register’, and that ‘rapporteurs, shadow rapporteurs and committee chairs shall publish online, for each report, all scheduled meetings with interest representatives falling under the scope of the Transparency Register’ (italics ours). The fact that this transparency provision is not mandatory for all MEPs raises several concerns. Remarkably, it may affect the homogeneity and completeness of the information provided by legislators. Moreover, it may incentivize some MEPs to strategically complying with this provision to point out others who do not provide information, and/or to highlight (or omit) information on meetings with interest groups that might affect their reputation (Braun and Busuioc, 2020). While it could be argued that the type of transparency addressed in this study is distinct in nature, we find justification in our analysis as the EP provision resembles a targeted transparency model of regulation that seeks to reduce information asymmetries among legislators, stakeholders and the general public (Bunea, 2018). In this respect, our research question is relevant as it addresses how a parliamentary transparency innovation is translated into legislators’ choices to disclose information on their interactions with interest representatives. While our study does not discern if MEPs’ behaviour is driven by strategic considerations, the analysis provides insights on how formal procedures as well as certain ideational-related rules affect legislators’ decision to inform about their meetings. © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. 4 Nuria Font and Ixchel Pérez-Durán II. Theoretical Framework: Institutions and Legislative Behaviour This study engages with institutional theory by emphasizing the role of rules structuring social interactions and shaping political behaviour (North, 1990; Ostrom, 1986). We adopt a commonly accepted conceptualization of rules as formal and informal prescrip- tions specifying the actions that are required and permitted, as well as the incentives and constraints for individuals’ behaviour (North, 1990; Ostrom, 1986). While institu- tionalist theorists have profusely elaborated on the distinction between formal and infor- mal rules (for example Helmke and Levitsky, 2004), we adopt a broad conceptualization by which formal rules are codified norms (North, 1990) – such as constitutions, laws and procedures – that are created and enforced by official channels (Helmke and Levitsky, 2004). By contrast, informal rules are unwritten, non-codified norms – namely traditions, conventions and values – that are created and enforced outside of official chan- nels (Helmke and Levitsky, 2004). We share the widely accepted assumption in institu- tionalist theory that formal and informal rules shape political behaviour (Helmke and Levitsky, 2004; North, 1990) and posit that rules affect MEPs’ choices regarding being transparent about their meetings with interest group representatives. For the identification of such rules, we borrow arguments from comparative research on government account- ability and transparency, and formulate hypotheses on legislators’ incentives to publish their contacts with interest groups. Formal Transparency Rules Research on interest groups in the EU has widely analysed how the interactions between legislators and interest groups are structured. From these studies, we know that interest groups seek to target legislators with the expectation of increasing their influence in policy-making (Ibenskas and Bunea, 2020). In turn, decision-makers depend heavily on interest groups for the formulation of policies as these groups provide legislators with technical expertise, valuable information, and venues for societal and economic support (Bunea, 2018), as well as information on the potential policy implications derived from the policy issues to be negotiated (Ibenskas and Bunea, 2020). Yet the intensity of inter- actions between legislators and group representatives varies depending on the distribution of legislative influence among legislators (Marshall, 2010). Understandably, lobbying ac- tivity is focused mainly on influential MEPs (Klüver et al., 2015; Marshall, 2010). MEPs in positions that influence policy—committee chairs, rapporteurs or shadow rapporteurs —enjoy considerable weight in legislative policy-making (Ibenskas and Bunea, 2020) by holding agenda-setting powers and playing a key role in both intra- and interinstitu- tional legislative bargaining. For example, EP committee chairs organize legislative tasks in committee meetings; rapporteurs prepare draft reports on legislative proposals; and shadow rapporteurs supervise rapporteurs’ work and report to their political groups on the progress of negotiations (Klüver et al., 2015). For the above-mentioned reasons, MEPs formally involved in policy-making are at the center of transparency concerns. In fact, Rules of Procedure on legislators’ reporting on their meetings with interest group representatives impose more-stringent requirements on MEPs with a policy influence position compared to those who do not hold such posi- tions. According to the EP Rule of Procedure 11, reporting on meetings with organized © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. Legislative transparency in the European Parliament 5 groups is mandatory for committee chairs, rapporteurs and shadow rapporteurs, while it is only voluntary for MEPs not holding any of these positions. Hence, MEPs with a policy influence position are more constrained to be transparent on their meetings with interest group representatives. In short, they have more incentives to follow rules and to avoid the potential costs associated with non-compliance. While formal rules on legislators’ transparency do not establish sanction mechanisms for non-compliance, MEPs with a pol- icy influence position are more easily subject to public scrutiny regarding their interac- tions with lobbyists. As a result, they may be more concerned about behaving in a manner that dispels suspicions of legislative opacity and capture, minimizing the reputational costs entailed in non-compliance (Carpenter and Krause, 2012) or strategically pointing other legislators out for not providing such information. H1. MEPs who have a formal policy influence position are more likely to inform on their meetings with interest group representatives than MEPs without this formal position. Parties’ Position on the Cultural Dimension Building on institutional theory on informal rules (Helmke and Levitsky, 2004) and on previous empirical studies on the impact of formal and informal rules on political behav- iour (for example Kaufmann et al., 2018), this study assumes that political ideology can be conceptualized as an informal rule guiding legislators’ behaviour. This assumption is justified by the conception of party ideology as a compendium of traditions that provide legislators with information, values and norms of behaviour guiding policy areas (Eder et al., 2017). Other than this, while core party ideology is generally specified in party stat- utes or manifestos, one can hardly conceptualize this as a formal rule with similar creation processes and enforcement mechanisms as constitutions, laws or procedures. Moreover, in the EP context, legislators are not formally obliged to follow their party’s positions and may behave in a way that contradicts them. In this respect, and as the abundant re- search on party cohesion reveals, MEPs whose behaviour goes against the party’s posi- tion may be sanctioned by party leadership through not necessarily formally established enforcement mechanisms, such as control over the candidate selection process (Carey, 2007; Hix, 2004) and leadership rewards and sanctions (Bressanelli et al., 2016). Research on legislative behaviour in the EP has demonstrated that parties’ ideological position structures political conflict and influences legislative behaviour (Hix, 2004; Hix et al., 2006). Yet the question of whether and how party ideology affects legislators’ trans- parency has received scant attention. To address this question, we rely on the idea that the cultural dimension GAL (green, alternative, libertarian) and TAN (traditionalist, authori- tarian, nationalist) is intensifying in structuring transnational party competition beyond the traditional left–right cleavage (Hooghe and Marks, 2018; Polk et al., 2017). The GAL/TAN dimension emphasizes that parties can be classified in terms of ‘their views on democratic freedoms and rights’. From this perspective, more libertarian (GAL) parties are more likely to support ‘expanded personal freedoms’, such as greater democratic par- ticipation, whereas more authoritarian (TAN) parties are more likely to reject such free- doms and rights (Hooghe et al., 2010). As policy agendas of libertarian parties may more easily emphasize the role of the expansion of the freedom and the right to know over the © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. 6 Nuria Font and Ixchel Pérez-Durán secrecy of the public domains, MEPs from parties closer to the libertarian positions would be more concerned with the need to provide information on the link between private in- terests and public policy. An additional argument would point to the idea that green parties are more concerned about the lack of democratic transparency in the EU (Hooghe et al., 2002) and are internally more democratic (Rüdig and Sajuria, 2020). On this basis, MEPs from GAL parties are expected to have more incentives to disclose information on the connections with interest groups than those from TAN parties. H2. MEPs from parties with more libertarian (GAL) positions are more likely to inform on their meetings with interest group representatives than those from parties with more author- itarian (TAN) positions. Party’s Populist Stance Populist parties have gained more presence in parliaments and in governmental office in recent years. To qualify populist parties, we rely on Mudde’s (2007) well-established def- inition conceiving populism as a ‘thin ideology’ not expressing core beliefs, but conceiv- ing that society is divided into two homogeneous and antagonistic groups, the ‘pure peo- ple’ versus the ‘corrupt elite’. By emphasizing anti-elitism, people-centrism and moral integrity (Böhmelt et al., 2022), recent research has identified parties for which populism is a constitutive ideational element (Zulianello, 2020). For the purpose of this study, this ideational approach allows the conceptualization of party’s populist views and discourses as informal rules guiding behaviour. We build our expectation on research addressing the association between populism and core aspects of democratic governance, namely direct democracy, transparency, po- litical participation and substantive representation. A first argument could lead us to ex- pect that populism increases transparency as populist parties promote the introduction of referendums to enhance the power of the people (for example Mudde, 2007), which can be connected with the idea that elected elites are not transparent and should be held at check (Gherghina and Pilet, 2021). However, research examining the connection be- tween populism and transparency would lead us to support the opposite expectation. In this respect, Fenster (2017, p. 173) develops two meanings of transparency in the cur- rent wave of populism and open government: ‘technocratic transparency’ – referring to the provision of information on certain types of documents and meetings – and ‘trans- parency in people’ – referring to the notion of populist transparency and emphasizing the moralistic claim of ‘authenticity and honesty’ (Roelofs, 2019). Since populist parties are more likely to adopt the moralistic conceptualization of transparency, the provision of specific information would not necessarily represent a core measure to be adopted. As regards transparency praxis, Juon and Bochsler (2020) find a negative impact of pop- ulists across several institutional safeguards, namely the rule of law and state transpar- ency. In a similar vein, Huber and Ruth (2017) find that populists in opposition may claim to continue their mission to increase transparency, whereas this claim is weakened when they enter in government. On this basis, legislators from populist parties typically demand transparency to mainstream parties but do not necessarily deliver transparency themselves. © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. Legislative transparency in the European Parliament 7 An additional argument to support our expectation builds on research on the interac- tions between populist parties and interest groups. In this respect, Berkhout et al. (2021) find that interest groups have much less interaction with populist parties compared to non-populist parties. While legislators from populist parties may prefer to in- teract with ‘the pure people’, they are more reluctant to interact with the so-called ‘corrupt elite’ (Mudde, 2004, p. 543). In addition, interest groups would also have less incentives to interact with populist parties, as ‘they may not want to alienate existing, mainstream friends’ (Berkhout et al., 2021, p. 422). Consequently, both the reluctance of populist leg- islators and the lack of incentives of interest groups can lead MEPs from populist parties to avoid making visible such (potentially scarce) interactions. H3. MEPs from populist parties are less likely to inform on their meetings with interest group representatives than those from non-populist parties. Corruption-Mitigation Tradition The relationship between government transparency and corruption mitigation has largely been addressed by comparative research on political corruption and democratic account- ability (for example Brusca et al., 2018; Lindstedt and Naurin, 2010). Most related re- search emphasizes that the contextual and cultural characteristics of political and admin- istrative regimes are core determinants of the attitudes of politicians and bureaucrats (Pasquier and Villeneuve, 2007). In particular, previous studies on government transpar- ency show that transparent behaviour can be rooted in non-written rules grounded in socio-political factors and national culture (for example Meijer, 2013; Kaufmann et al., 2018). That is, while there are several long-standing traditions by which public access to information has been widely spread, in other traditions, secrecy and corruption are comparatively more tolerated (Ogus, 2004). In this respect, some studies highlight the re- lationship between a culture of tolerance of corruption and government transparency (Bauhr and Grimes, 2017). In those democracies where public access to decision-making is a key component, transparency is seen as an element of good gover- nance (Meijer, 2013), a fundamental right of citizens and an instrument to hold the gov- ernment accountable (Grønbech-Jensen, 1998). From this perspective, political corruption at the national level might affect how legis- lators in the EP provide transparent information about their interactions with interest-group representatives. This expectation is based on the idea that corruption is re- lated to the cultural, social and administrative contexts in which it operates (Dunlop et al., 2020), and that political systems that have designed mechanisms to mitigate corrup- tion effectively have more propensity to provide information on the contacts between pol- iticians and interest groups. We argue that the tradition of national corruption mitigation in which MEPs had been socialized before serving in the EP translates into different attitudes towards transparency once they become Members of the EP. In other words, national tra- ditions of corruption mitigation are expected to travel with MEPs and translate into their varying attitudes on legislative transparency. In particular, we expect that legislators from countries with stronger traditions of corruption mitigation are more likely to perform trans- parently compared to those from countries with weak corruption-mitigation regimes. © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. 8 Nuria Font and Ixchel Pérez-Durán H4. MEPs from countries with stronger corruption-mitigation traditions are more likely to inform on their meetings with interest group representatives than MEPs from countries with weaker corruption-mitigation traditions. III. Data and Methods The study is based on a dataset containing data on MEPs serving during the first two years of 9EP, from 2 July 2019 to 30 June 2021, who were active in June 2021. The dataset comprises MEPs serving during the full period under study as well as those becoming leg- islators once the legislature had started.1 Covering a two-year period of legislative activity provides sufficient time for policy-makers to interact with interest group representatives and to report on those meetings. A similar approach is taken by several previous studies examining legislative behaviour in the EP (for example Hix et al., 2012). Other than this, while in June 2021 there were 705 active MEPs, due to data restrictions on party ideolog- ical positions (see below), the analysis includes 656 legislators. Our dependent variable indicates whether an MEP publishes her or his meetings with interest group representatives on the EP website at any time during the period examined. The variable takes the value 1 when meetings are reported and 0 otherwise. Data were re- trieved from the official MEPs’ personal profiles on the EP website.2 Here some clarifica- tions are needed. First, while the value 1 of our dependent variable indicates that meetings with interest groups were held, concerns about whether the variable takes the value 0 be- cause MEPs do not report their meetings or because they do not hold meetings may arise. We are confident in assuming that not publishing information regarding meetings with in- terest group representatives is not systematically associated with the absence of meetings. This assumption is based on the data from the 2015 European Parliament Research Group MEP survey (Whitaker et al., 2016) showing that less than 1 per cent of the MEPs responding to the survey indicated that they had no contact with any interest-group types they were asked about. This indicator supports the assumption that a very high percentage of MEPs establish contact with interest group representatives. Hence, when the dependent variable takes the value 0, it might reflect a refusal to follow the transparency rules instead of indicating that the MEP had no such meetings. Second, a dichotomous variable provides information on whether legislators behave transparently or not. Our data show that 53 per cent of MEPs published their meetings at some time during the period under study (for more descriptive details on the dependent variable, see Figures S1 and S2 in the Appendix). Our design does not take the number of meetings published by MEPs as the main dependent variable. While a count variable would provide a measure of the intensity of reported meetings, a higher number of re- ported meetings does not necessarily involve a higher degree of transparency – not to mention that the list of meetings may not be comprehensive. With these caveats in mind, a count of meetings is used as a dependent variable to perform an additional robustness check. Data were provided by Transparency International EU. 1 Following the UK’s withdrawal from the EU on January 2020, 27 seats were redistributed to other countries. For this rea- son, UK MEPs are not included in the analysis. 2 https://www.europarl.europa.eu/meps/en/full-list © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. Legislative transparency in the European Parliament 9 Regarding the operationalization of independent variables, the formal transparency rule is operationalized with a binary variable indicating whether MEPs are committee chairs, rapporteurs of legislative dossiers or shadow rapporteurs (yes = 1; 0 = otherwise). Note that the same MEP may meet with interest group representatives in the capacity of chair, rapporteur or shadow rapporteur or in her or his individual capacity. As our unit of analysis is the individual MEP and not the individual meeting, an MEP with a policy in- fluence position takes the value 1, irrespective of whether she or he holds meetings in the capacity of chair, rapporteur or shadow rapporteur, or in the capacity of a Member. For the operationalization of party ideological position on the cultural dimension, we use the GAL/TAN scores of the 2019 Chapel Hill Expert Survey (CHES) (Bakker et al., 2020). The score ranges from 0 to 10, where 0 indicates green/alternative/libertarian and 10 indicates traditionalist/authoritarian/nationalist. CHES data are suitable for our study as they provide scores on the ideological positions of parties based on expert judge- ments (for example Ibenskas and Bunea, 2020). We use MEPs’ party affiliation at the start of 9EP. For those parties not covered in the 2019 wave, we employ the scores from the 2014 CHES (Polk et al., 2017). Still, 49 MEPs are excluded from the analysis either be- cause they were members of one of the 21 parties not coded in any of the two CHES waves employed (see the list of these parties in the Appendix), or because they have no party affiliation.3 To provide a more nuanced view of the effect of different dimensions of party ideology, we alternatively employ the CHES general left–right score. For populist party, we rely on Rooduijn et al. (2019) and create a binary variable taking the value 1 for populist parties and 0 for non-populist ones. As an alternative operationalization, and based on CHES data, a binary variable takes the value 1 when the ‘anti-elite rhetoric’ is coded in the survey as the first, second or third most important party issue, and 0 otherwise. We employ the 2019 World Bank’s Worldwide Governance Indicators (WGI) Control of Corruption (CoC) (Kaufmann et al., 2010) for the 27 Member States as a proxy for na- tional corruption. The index captures perceptions of the extent to which public power is exercised for private gain, including both petty and grand forms of corruption as well as “capture” of the state by elites and private interests. The measure is calculated employing data sources that provide perceptions from business, experts and citizens’ sur- veys. The scores for EU countries range from 50 to 99, with lower values indicating less control of perceived corruption and higher values reflecting greater control of perceived corruption. The CoC index is preferred to the Corruption Perceptions Index provided by Transparency International (Lambsdorff, 2008), although in more practical terms, both scores are almost perfectly correlated (Pearson’s r = .98 at p < .001). We discard the Free- dom House measure on the functioning of government, which addresses the question of government openness and transparency, as it does not offer sufficient variation for EU-27. Several controls are included. Since control of corruption could be closely associated with other national indicators, we include several country-level controls. We use the V-Dem liberal democracy index for 2019 to control for the level of democracy. Using Standard Eurobarometer 91 (spring 2019) data, citizens’ attitudes towards the EU is 3 While it would be desirable to cover all MEPs, we consider that excluding those from parties not coded by the CHES and performing the analysis with 93 per cent of MEPs is preferable to imputing a value of the party we would consider having more ideological proximity with the MEP’s position. © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. 10 Nuria Font and Ixchel Pérez-Durán controlled for: national scores on ‘trust in the EU’ and ‘image of the EU’ are alternatively employed. GDP per capita is also included as a control. Based on previous findings showing that the type of electoral list system affects legis- lators’ behaviour regarding party unity (Carey, 2007; Hix, 2004) and, more particularly, that MEPs elected under flexible and open list systems are more likely to recognize inter- est group organizations (Ibenskas and Bunea, 2020), we control for the type of electoral list system. A binary variable takes the value 1 in the case of closed-ballot systems and 0 in the case of open/Single Transferable Vote systems. Given the association between gender representation and corruption found in the liter- ature, we also control for gender. This is important because research on the gender gap shows that greater representation of women in parliament is associated with lower degrees of corruption (Dollar et al., 2001; Esarey and Chirillo, 2013), that women disapprove of corruption more than men; and that female participation in government reduces the degree of perceived corruption (Esarey and Chirillo, 2013). We also control for the age of the MEP and for whether the MEP had served during the previous term (incumbent = 1; other = 0). Younger MEPs are expected to behave more transparently since ‘digital natives’ are assumed to be more in tune with information-sharing and are more socialized to be transparent. As incumbents have longer experience in serving in the EP, they may be highly socialized regarding transparency ini- tiatives in the parliamentary arena. Finally, fixed effects for European Political Groups (EPGs) are included in all regression models. Table S1 in the Appendix summarizes the descriptive statistics. We perform several robustness checks on the independent and dependent variables, on the sample and on the model. Robustness checks taking the COVID-19 period are also performed. We believe the study of legislative behaviour during 9EP, and, in particular, legislators’ reporting on their meetings with interest group representatives cannot ignore the pandemic context. The COVID-19 disease was recognized as a global pandemic by the World Health Organization on 11 March 2020, and most EU national governments de- creed mobility restrictions and issued stay-at-home recommendations. Regarding EP ac- tivity, the pandemic likewise imposed mobility restrictions on MEPs, minimized their face-to-face interactions with interest group representatives, and imposed remote-working conditions. We perform robustness checks to observe whether MEPs who published information before the pandemic maintained their reporting activity during the pandemic period. IV. Analysis As our dependent variable is dichotomous and given that MEPs are nested in national parties and countries, we perform a multilevel logistic regression with random effects for national parties and countries. We perform two models: Model 1 includes the indepen- dent variables and Model 2 adds the controls (see Table 1). The results confirm H1 on the effect of the formal rule of procedure on legislators’ transparency performance. The odds ratio indicates that MEPs influencing policy-making – committee chairs, rapporteurs and shadow rapporteurs – are significantly more likely to report on meetings with interest representatives. Based on Model 1, we calculate the prob- ability of MEPs publishing meetings with interest representatives, keeping continuous © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. Legislative transparency in the European Parliament 11 Table 1: Multilevel Logistic Regression on Legislative Transparency (Odds Ratio) Independent Variables M1 M2 Policy influence 3.01*** (0.77) 2.95*** (0.76) GAL/TAN 0.8** (0.08) 0.8** (0.08) Populist party 1.02 (0.48) 0.98 (0.46) Control of Corruption 1.07*** (0.02) 1.07** (0.03) Controls Liberal democracy index 0.07 (0.17) Trust in EU 0.99 (0.02) GDP per capita 1.01 (0.001) List system (closed) 1.03 (0.45) Gender (female) 1.78** (0.42) Age 0.99 (0.01) Incumbent 0.79 (0.19) Fixed effects EPG yes yes Random effects Estimate (se) Estimate (se) Country 0.49 (0.34) 0.37 (0.29) National party 0.63 (0.35) 0.61 (0.36) Constant 0.01*** (0.02) 0.06 (0.03) Log likelihood 301.631 295.846 AIC 631.262 633.692 BIC 694.068 727.901 N 656 656 *** p < 0.01, **p < 0.05, *p < 0.1. Standard errors in parentheses. variables at their means and binary ones at their modes (see Figure 1). The probability of publishing meetings moves from 0.43 for MEPs without policy influence positions to 0.69 for those holding such positions. In other words, the probability of being transparent increases by 61 per cent when there is a compulsory stipulation constraining legislative behaviour. The results confirm H2 on the effect of parties’ GAL/TAN position on legislative transparency (Model 1 and Model 2). MEPs from GAL parties are significantly more likely to report their meetings with interest representatives than legislators from TAN parties. As GAL parties are more concerned about legislators serving private interests and about democratic accountability values, MEPs from these parties are more incentiv- ized to be transparent as a way to voice critical views about politicians with dense con- nections to private interests and as a way to be consistent with their parties’ emphasis on democratic accountability. Based on Model 1, Figure 1 plots the predicted probability of GAL/TAN on legislative transparency at its minimum and maximum values, keeping continuous variables at their means and binary ones at their modes. The probability of legislative transparency decreases from 0.84 for parties closest to the GAL pole to 0.35 for parties closest to the TAN pole. That is, the probability of legislative transpar- ency decreases by 58 per cent between MEPs from GAL and TAN parties. When using the left–right dimension alternatively, the predicted probability of transparency de- creases by 35 per cent, moving from 0.85 for extreme left parties to 0.52 for extreme right parties. In sum, GAL/TAN has a stronger effect on transparency than the left–right ideological stance. © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. 12 Nuria Font and Ixchel Pérez-Durán Figure 1: Predicted Probability of Legislative Transparency, 95 per cent CIs [Colour figure can be viewed at wileyonlinelibrary.com] H3 on the effects of populist parties on legislative transparency is not confirmed. The results confirm H4 on the effects of national corruption. As Model 1 and Model 2 show, perceived control of corruption has a significant and positive effect on legislators’ trans- parency regarding their meetings with interest group representatives. The results suggest that national tradition of corruption mitigation translates into legislators’ transparency performance in the EP. Based on Model 1, Figure 1 shows the predicted probability of legislative transparency for the minimum and maximum levels of perceived control of corruption, keeping continuous variables at their means and categorical ones at their modes. The probability of MEPs reporting their contacts with group representatives moves from 0.21 for MEPs from countries with the lowest degrees of control of corrup- tion to 0.87 for those with the highest degrees of control of corruption. That is, the prob- ability of publishing meetings increases by 315 per cent between MEPs from countries with the lowest levels of control of corruption and those with the highest. The core results of analysis remain practically unchanged when including controls. Model 2 shows that female legislators’ likelihood of performing transparently is signifi- cantly higher than that of their male colleagues. Robustness Checks We perform robustness checks on independent variables, on the dependent variable, on the model and on the sample. Regarding the independent variables, we employ the © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. Legislative transparency in the European Parliament 13 Corruption Perception Index provided by Transparency International as an alternative measure of national corruption, and the alternative operationalization of populist party described in the method section. The results remain practically unchanged. We complement our core analysis with an alternative dependent variable taking the count of meetings published by MEPs. Given that the dependent variable is discrete and non-negative, we perform a multilevel mixed-effects negative binomial regression with random effects for national parties and countries. The results, reported as exponentiated coefficients, are in line with our core findings with the exception of age, as younger legislators report more meetings (see Table S2 in the Appendix). Finally, we replicate the analysis taking MEPs who reported meetings with interest group representatives before the COVID-19 outbreak and checking whether the accounts for transparency hold afterwards (see Tables S3 and S4 in the Appendix). The interpretation of the results must be made cautiously as they are only suggestive of how MEPs behaving transparently before the pandemic outbreak continued to do so afterwards. The analysis is in line with our core findings, also suggesting that younger MEPs who provided information about their meetings before the COVID-19 outbreak are significantly more likely to continue doing so afterwards. Discussion and Conclusion This study identifies the conditions under which MEPs are more likely to publish information on their meetings with interest group representatives. The study engages with institutional theory by assuming that certain formal and informal rules incentivize and constrain legislators when faced with the decision of whether or not to publicize their contacts with interest groups. Borrowing arguments from the literature on government transparency, and contextualizing them in the study of legislators’ incentives and behaviour in the EP, our findings contribute to bridge research on legislative behaviour and on government transparency by showing that parliamentary procedural rules, parties’ position on the cultural dimension, and national corruption tradition affect legislators’ propensity to disclose information about their meetings with interest representatives. Our findings show that MEPs for whom transparency rules are mandatory – committee chairs, rapporteurs and shadow rapporteurs – are more likely to inform on their meetings with interest representatives. The results are indicative that formal parliamentary rules constrain legislators’ behaviour when deciding to publish their meetings. Arguably, as EP transparency rules shine a spotlight on legislators with policy influence positions, they are incentivized to publish their meetings with interest groups as a way to dispel concerns about legislative capture and to minimize reputational costs derived from the potential suspicion of opaque transactional agreements with private interests. Our results also reveal that MEPs from GAL parties are more inclined to publish infor- mation on their contacts with group representatives, compared with those legislators from TAN parties. By emphasizing the expansion of personal freedoms, libertarian parties might be more responsive to the request of making public information about their © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd. 14 Nuria Font and Ixchel Pérez-Durán meetings with interest parties. This finding adds to research on the relationship between ideology and government transparency (for example Smirnova, 2018) and engages with the novel argument in the literature on EU lobbying on the relationship between ideolog- ical affinity and MEPs’ recognition of interest groups (Ibenskas and Bunea, 2020). More precisely, the analysis contributes to bridge research agendas on the transnational cultural dimension and on legislative transparency, and indirectly engages with the discussion of whether the GAL/TAN dimension has become a dominant one in structuring conflict and affecting legislative behaviour in the EP. Finally, the analysis shows that national corruption, understood in this study as an in- formal rule deeply embedded in culture and tradition, influences legislative transparency in the EP. We show that MEPs from countries with a strong regime of corruption mitiga- tion are more inclined to publish their meetings with interest groups, than those from countries with lower corruption-mitigation credentials. While comparative research on corruption has widely investigated whether government transparency contributes to the mitigation of corruption, our study considers the national corruption culture in which MEPs were (in principle) socialized as an independent variable. It shows that national cor- ruption regimes matter for legislative transparency, as they travel with MEPs to Brussels/ Strasbourg and are translated into legislators’ behaviour. The finding contributes to previ- ous research on transparency and legislative behaviour in the EU by showing that infor- mal norms on corruption in which MEPs were socialized domestically matter for legisla- tive transparency at the EU level. The results of this study contribute to the literature on legislative transparency by identifying conditions increasing the probability that MEPs report on their meetings with interest representatives. Yet the limitations of the analysis cannot be neglected. Importantly, research on interest group provides insights on the ‘ties that count’ when it comes to explain which groups gain access to policy makers (for example Beyers and Braun, 2014). In this regard, our study is limited to the analysis of who reports, leaving out the core question of the comprehensiveness and relevance of the meetings reported. Similarly, as the list of organizations included in the Transparency Register is incomplete, MEPs may discard informing on meetings with non-listed organizations. Moreover, they may omit meetings with organizations (either registered or not) that could harm their reputation (for example Braun and Busuioc, 2020). Further research will benefit from addressing these issues and from analysing whether legislative trans- parency is influenced by the type of interest group and the policy field, thus engaging with current studies investigating how interest groups’ attributes affect their interac- tions with EU institutions (for example Alves, 2020). In addition, a qualitative analysis would help understanding legislators’ main motivations to provide information and dis- cerning whether reporting on meetings reflects convictions about transparency or is strategically employed. From a different perspective, investigating citizens’ responses to legislative transpar- ency is a promising line of research. In particular, addressing whether legislators’ propen- sity to be transparent increases when meeting dates approach the EP election, a time when public scrutiny of legislators’ work may increase, would provide insights on the connec- tion between legislative behaviour and electoral incentives. Moreover, the study of the legislative footprint should be extended to the three main EU institutions within the con- text of the Interinstitutional Agreement (the EP, the Council and the Commission) on a © 2022 The Authors. 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Supporting Information Additional supporting information may be found online in the Supporting Information section at the end of the article. Figure S1. MEPs’ reporting on meetings with interest group representatives, by country (%) Figure S2. MEPs’ reporting on meetings with interest group representatives, by European Political Group. Table S1. Descriptive statistics of the dependent, independent and control variables Table S2. Multi-level mixed effects negative binomial regression Table S3. MEPs publishing meetings with interest groups before and during COVID-19 crisis Table S4. Multilevel logistic regression on legislators’ transparency during the COVID- 19 crisis (odds ratio) © 2022 The Authors. JCMS: Journal of Common Market Studies published by University Association for Contemporary European Studies and John Wiley & Sons Ltd.