The Three Faces of Populism in Power: Polity, Policies and Politics

Abstract In this article, we explore the consequences of the increasing presence of both left- and right-wing populist parties in government, critically reflecting on the recent scholarship on the topic, underlining promising venues for future research and outlining a conceptual framework which constitutes the background of this special issue entitled ‘Populism in Power and its Consequences’. Our main contribution is empirical, since – by reflecting on the various articles hosted in the special issue – we assess the impact of populist parties in government on politics, polities and various policy domains. We also provide an account of potential moderating factors of the influence of populists in government, focus on different ideological underpinnings of types of populisms (left-wing and right-wing) and discuss their relevance. We conclude by identifying four possible scenarios for European populist parties in governments: radicalization, compromise and moderation, splintering, or loss.

In this special issue, we are interested in exploring the consequences of the increasing presence of both right-and left-wing populist parties in government (Mudde 2013). 1 In recent years, populism has been the subject of unprecedented levels of media attention, political contestation and scholarly articles. 2 Between 1990 and 2000 the Google Scholar citations database registered 21,900 entries using 'populism' as a keyword; in the following decades (2001-11 and 2012-21), the results were 55,500 and 73,000, respectively. 3 Although conflicting definitions of the phenomenon and explanations of its causes persist, as well as efforts to measure it (Norris 2020), there is an increasing and promising scholarly debate on what happens once anti-elitist and people-centred populists are in power. The articles of the special issue address key analytical and research aspects of this critical question. Furthermore, our contribution is aimed at widening the traditional scope of analysis by focusing on populist parties that are rarely covered togetherthat is, we include left-wing (or inclusionary) and right-wing (or exclusionary) populist parties, as well as hybrid cases in this special issue.
With populist parties becoming increasingly relevant, there has been a rise in studies on the impact of populists' electoral success on several political domains, including: the party system, institutions, the other mainstream parties, media debates and public opinion, policymaking, political participation and various aspects associated with the quality of democracy (Akkerman et al. 2016;de Lange 2012;Huber and Schimpf 2017;Juon and Bochsler 2020;Mudde 2013;O'Donnell 1994;Pribble 2013;Rooduijn et al. 2014;Taggart and Rovira Kaltwasser 2016). Some scholars see populism in power as a danger for the constitutional foundations of liberal democracies (since it supposedly speaks with a 'homogeneous' voice), such as pluralism and the protection of minorities (Abts and Rummens 2007); others instead claim that populist actors could actually correct some democratic deficiencies (Mudde and Rovira Kaltwasser 2017), bringing back people to be interested in politics and responding to neglected or depoliticized demands (Kriesi 2018). In this study we argue, in line with others (Muis and Immerzeel 2017), that whether populist parties have an impact on various outcomes associated with the quality of democracy is a theoretical question that can be empirically tested.
In this contribution and in the special issue we refer to the scholarship on the implications of the success of populism by looking through comparative case studies and methodological pluralism at some European (EU) and non-European cases of populism in government and their impact on several political domains: polity (the definition of the boundaries of the political community, the institutional settings of political systems); policies (policy positions and adoption); politics (the actors of the political system and their interactions). This allows us to discuss critically in a coherent and original way existing studies on the topic. Indeed, it is important to emphasize that these three domains carry relevant implications for how populism should be defined, how it can be explained and how it should be studied empirically.
The research question appears socially and politically, as well as scientifically, relevant. First of all, it should be noted that there has been a consistent increase of populist parties in government since 2000. If in the turn of the millennium participation of these parties in government was limited to two small European countries (Switzerland and Slovakia), at the beginning of 2021 it amounted to 10 countries. 4 Populist parties were in government as main coalition partners in Hungary (Fidesz), Poland (Law and Justice -PiS), Italy (Five Star Movement) and Czech Republic (Ano). As junior coalition partners, in early 2021 populist parties were present in Italy (Lega), Spain (Podemos) and Switzerland (Swiss People's Party). Lastly, in Denmark, the Danish People's Party, despite not being a member of cabinet, provided external parliamentary support to the government until 2019, 5 and populist parties held government posts during the previous decade or so in Austria (Freedom Party of Austria -FPÖ), Greece (SYRIZA and ANEL), Norway (Progress Party) and Finland (True Finns and Blue Reform). Given this European political landscape, exploring what populist parties do once in power and what are the consequences of their populistic political projects appears extremely useful and timely.
Scientifically, the topic merits full attention. First of all, in Europe, unlike in other historical periods and in other parts of the world, populism in power is a relatively new phenomenon. Second, most of the scholarship which looks at the consequences of populists' success (being in government or having achieved an electoral breakthrough that puts them in an influential agenda-setting position, such as Podemos before entering the cabinet) mainly focuses on right-wing populism (Mudde 2016). Third, we lack a full assessment of the post-financial crisis wave of left-and right-wing populists in power in European politics. 6 In addition, whereas debates about radical right populism often focus on Central and Eastern Europe, empirical research mainly looks at Western countries. Also, although increasing in Europe as well, this research area on populism is relatively less studied than other fields (such as those related to the causes, definitions and measurements of the phenomenon) and therefore is in need of more empirical studies which could help the elaboration of more nuanced hypotheses and theories for the understanding of the object. The (relatively) recent special issue edited by Paul Taggart and Cristóbal Rovira Kaltwasser (2016) considers the impact dimension but is constituted as a set of case studies which do not cover all the three dimensions we focus on in our contribution. Comparative studies across different types of populisms in power are in general rare (for exceptions Fenger 2018;Huber et al. 2021;Lutz 2018) and the empirical evidence offers contrasting results of their impact once they take governmental positions. Finally, with regard to populism's outcomes, some political domains are more studied than others; with the exception of certain policies (such as, for example, immigration and integration policies), the policy positions and policies implemented by these actors are still relatively under-researched, compared to their discourses.
This special issue contributes to the literature both theoretically and empirically. Through our cross-national and cross-organizational comparison, focusing primarily on (both Western and Eastern) Europe, we aim at expanding descriptive and explanatory knowledge on European populism and its potential influence across the right-left spectrum. Furthermore, from an empirical perspective, we also include cases from the US, the Middle East and South America.
The specific questions addressed are the following: 1. Once in government, do populist parties maintain their populist features and ideological characteristics? 2. Do the populist parties translate their populist traits (for example, a specific conception of the people) into specific policies? 3. How do these parties influence and eventually reshape the party system and the existing mainstream parties? 4. Do populist parties have an impact on citizens' values and opinions? 5. How much influence do the populist parties exercise on the main political institutions? 6. Finally, how are populist parties related to political dissatisfaction and disaffection, citizens' values and political behaviour?
In this contribution and throughout the special issue we will try to answer these questions. Following previous scholarship (e.g. Mudde and Rovira Kaltwasser 2012), we are not interested only in understanding the degree and forms of the consequences of populism in power, but we also try to suggest some guidelines for its analysis, reflecting on common mechanisms across countries and/or types of populisms, as well as on moderating (or enhancing) factors of its effects, at macro, meso and micro levels of analysis.
Populists in power: polity, policies, politics The different faces of populism have been heavily debated. Our point of departure is to consider the impact of populist parties in power as a function of the various political domains, while not ignoring the existence of potential mutual interferences. In terms of our notion of populism, while the definition of 'populist' remains contested, the calls of ordinary people against elites and for the rejection of intermediary representative institutions have been increasingly used by parties with different ideological underpinnings, discourses and organizational characteristics. Therefore, this special issue builds on the ideational approach (Mudde 2016).

Polity
The polity dimension usually refers to the institutional settings and constitutional foundations of a system, as well as unwritten rules which form the framework for the political sphere, including the political culture of a community. Some studies have looked at the consequences of populism in power on institutional changes (Bogaards 2018, on Hungary; Ruth 2018, on Latin America). It has been underlined that populist parties may have a substantial impact on the institutions of a country (such as parliament or constitution) and try to turn the liberal institutions of a democracy into an 'illiberal regime' (Pappas 2019). In particular, with regard to populism and the quality of democracy (Juon and Bochsler 2020; Mudde and Rovira Kaltwasser 2017; Norris and Inglehart 2019; Spittler 2018), some scholars have found evidence of positive effects in terms of representation and participation, namely a different type of democracy which strengthens popular control (Huber and Ruth 2017;Leininger and Meijers 2020), whereas others stressed various negative aspects (such as a decrease in quality of voice and accountability, rule of law, state transparency, an alteration of the system's checks and balances (Huber and Schimpf 2017;Juon and Bochsler 2020;Ruth 2018)). However, the impact is moderated by factors such as the populists' degree of government access and their ideology. From a political system standpoint, some studies also point to a potential revitalization of the political discourse on institutions at the national level as an effect of populist success: once under populist success, mainstream parties may emphasize the advantage of the existing political system, taking a decisively prodemocratic and pro-system position (Mauk 2020). The affinity of populist actors with majoritarian and direct democratic instruments has previously been noted (Urbinati 2019). When looking at the scholarship investigating the changes in populist parties once they enter governmental positions, the debate about populism's moderation versus radicalization comes into play (Akkerman and de Lange 2012;Albertazzi and McDonnell 2015;Krause and Wagner 2019;van Spanje 2010). 7 More specifically, what effect does their inclusion in a governing coalition have on populist parties, in terms of both their ideological positions and their electoral success? This is an important topic because of the anti-establishment agenda espoused by these parties. Findings show that once in power there is a tension between the parties' anti-elitist profile and their government responsibilities: these parties moderate their positions and become less populist (i.e. radical) in their programme after electoral successes, which normally results in electoral losses (Heinisch 2003;Rooduijn et al. 2014). However, the so-called inclusion-moderation thesis is not always confirmed (Akkerman et al. 2016): whereas some studies show a mainstreaming of populist parties in government (Drápalová and Wegrich 2020; Paxton and Peace 2021), other scholars stress the opposite, namely radicalization (see the concept of 'negative integration', Zulianello 2020) or ideological flexibility which follows the electorate's preferences (Bartha et al. 2020). Existing findings are predominantly related to right-wing or exclusionary cases (Zaslove 2012), since there are only a few and recent left-wing or inclusionary populist parties in government (e.g. SYRIZA between 2015 and 2019, and Podemos since 2020). 8 When looking at the definition of the identity and the boundaries of the political community, we find several studies on the consequences of populism which focus on the changes that populist parties can determine, in the long term, on citizens' values and attitudes, such as political opinions. In this regard, populist parties' success may have consequences at the individual level, as citizens might attach more importance to certain issues. However, the findings are controversial and provide a mixed picture (Dunn and Singh 2011;Semyonov et al. 2006; Sprague-Jones 2011): while some conclude that successful right-wing or exclusionary populist parties can undermine support for multiculturalism (Bohman 2011) or even the institutions of liberal democracies, thus fostering social and political polarization (Bartha et al. 2020;Grajczjár et al. 2022, in this special issue), others find these parties have no effects on tolerance. A more extensive study, based on European Social Survey (ESS) data , shows that exclusionary populist parties have not determined anti-immigration attitudes in Europe (Bohman and Hjerm 2016). In contrast, a recent study on the US (Hameleers 2020) illustrates how citizens' exposure to populist conspiracy theories used by Donald Trump has determined social polarization. 9

Policies
With regard to the scholarly debate on the influence of populism on policies, most studies focus on the extent to which populist parties are successful in implementing policies derived from their ideology (such as for right-wing or exclusionary populists: nativist, anti-immigrant, anti-integration policies: Akkerman 2012Akkerman , 2015Ennser-Jedenastik 2016;Han 2015;Heinisch 2003;Immerzeel and Pickup 2015;Luther 2011;Rooduijn et al. 2014;van Spanje 2010;Yılmaz 2012). Findings show that these parties have no or limited impact on migration policies. For example, Tjitske Akkerman's (2012) quantitative analysis comparing the immigration and integration policies of 27 cabinets of varying composition in nine countries (1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010) shows that populist radical right parties in office have stricter immigration and integration legislation than centre-left cabinets. However, when they are compared with centre-right cabinets no difference seems to emerge. Nevertheless, it has been shown that when in coalition with mainstream parties, (right-wing) populists, such as the Austrian Freedom Party and Lega Nord, can be instrumental in passing more restrictive immigration policies (Zaslove 2008). Therefore, their influence on immigration (as well as also integration) policies seems to be indirect (Akkerman 2015), as they move the political game in terms of immigration, multiculturalism, law and order, and so on. As these populist parties become successful, mainstream partiesby following a vote-seeking logicadapt to recapture part of the electorate lost (Yılmaz 2012). Put differently, in the medium term, the populist parties' rhetoric may determine changes in policies (Rinaldi and Bekker 2021).
This mechanism, not exclusively related to immigration policies (on agro-food policies, Sheingate and Greer 2020), can lead to adjustments and changes in the policy paradigm of any given country. However, research has so far focused on a limited number of policies (such as immigration, multiculturalism, integration)namely, on what seems to be the core of populists' discourse (i.e. cultural and identity-based issues: Röth et al. 2018).
Welfare policies have been found to be at the core of several populist parties' policymaking, either in its inclusionary or exclusionary form (Ennser-Jedenastik 2016Font et al. 2021;Rathgeb 2021;Busemeyer et al. 2021); however, so far the findings 10 are mostly associated with exclusionary populist parties (Biard et al. 2019;Ennser-Jedenastik 2018;Fenger 2018;Swank and Benz 2019). Chiara Rinaldi and Marleen Bekker (2021), for example, have shown that in Hungary and Poland right-wing or exclusionary populist parties in power shape social policy through their welfare chauvinism agenda, aiming at restrictions in provisions for immigrants and minority groups. The alleged link between populism and specific economic and fiscal policies (i.e. the notion of 'economic populism' in Latin America) has now been dismissed, but the aim of identifying some ideal-typical features of populist policy or style of policymaking still animates the research agenda of many scholars. 11 Furthermore, scholars have recently stressed the importance of distinguishing between direct and indirect influence of populist parties on public policy (Biard et al. 2019), 12 assessing the role of some explanatory factors, among which are the formal power enjoyed by populists in the political system (i.e. governmental position vs opposition) and the 'time' variable. Populist parties within government coalitions have a constrained influence on their own issuessuch as immigration policywhich becomes even weaker over time (direct influence). On the contrary, when populists are in opposition, they might exercise a 'blackmail potential', leading mainstream parties to shift their discourse and initiatives, as well as concrete policies, towards their demands (for example, in the Danish case; see McDonnell et al. 2021).
In conclusion, although it is a fruitful and growing line of research, the literature on the consequences of populism on policies still suffers from some empirical, classificatory and methodological challenges: the overall number of cases of populist actors covering strictu sensu decision-making roles is still relatively low (although increasing, as for example after the 2020 Polish elections), controversies among scholars on which parties should be considered as populist remain significant (Biard et al. 2019) and studies are mainly carried out at the national level, with a few exceptions at the local level (Bolin et al. 2014;Drapalova and Wegrich 2020;van Ostaijen and Scholten 2014). Moreover, so far, some policies have been less studied: for example, the effects of populist politics on gender equality policies have not yet attracted large attention (Kantola and Lombardo 2020), and only recently studies have focused on environmental policies, with right-wing populist parties associated with more permissive positions (Huber et al. 2021;Tosun and Debus 2020;Vihma et al. 2020).

Politics
One of the key dimensions where we register the influence of populist parties is on party competition, party systems and political participation. More broadly, we find that the politics dimension, focusing on the actors' struggles for power and their interactions, needs to be carefully considered when looking at the impact of populist parties in power.
The impact of populist parties on mainstream parties has been mainly investigated by looking at the changes in programmatic positions on important issues for populistssuch as immigration, multiculturalism, law and order, anti-establishment rhetoric and EU integration (Abou-Chadi and Krause 2018; Alonso and Claro da Fonseca 2012). Steven Wolinetz and Andrej Zaslove (2018) provide theoretical arguments and in-depth case studies of how populist parties across Europe affected mainstream parties, political systems and the competition within the political realm, stressing that while the impact is contained in rather more well-established party systems, in countries such as Italy the rise of populism has entailed much more dramatic changes. Franz Fallend and Reinhard Heinisch (2016) demonstrate how actors in Austria and abroad have reacted to the government participation of the FPÖ (ostracizing vs incorporating them) and the effectiveness of these different strategies. Tarik Abou-Chadi and Werner Krause (2018) offer empirical evidence on how, since the 1980s, mainstream parties in 23 European countries reacted to the entry of populist parties (mainly the radical right) with a policy shift towards populist positions.
In some cases, populists have a 'contagion effect' on other mainstream parties in the political system (to mention just two studies, see Akkerman 2015; Rooduijn et al. 2014), polarizing or radicalizing the content of the political debate as well as increasing the salience of certain issues. However, this topic is still rarely investigated empirically (Manucci and Weber 2017). This observation applies to both the right and the leftwhich can, for instance, accept Islamophobic perspectives to avoid a shift in its constituency towards the extreme right (Yılmaz 2012). Other studies find no evidence that mainstream parties have become more 'populist' and authoritarian (Mauk 2020).
Furthermore, looking at the consequences of populism on citizens' political behaviour is a prolific line of research (Bohman 2011;Dunn and Singh 2011;Immerzeel 2015;Semyonov et al. 2006;Sprague-Jones 2011;Wilkes et al. 2007; for the few comparative studies across varieties of populism, Juon and Bochsler 2020; Spittler 2018).
Regarding political involvement, participation and trust, it might be expected that populist parties increase voter turnout (Huber and Ruth 2017) because they are passionate mobilizers that fulfil a watchdog function and reintroduce electoral competition (Leininger and Meijers 2020;Schumacher and Rooduijn 2013). Populists in power are therefore expected to encourage disengaged people to become more involved in politics (Jansen 2011) and make them think that the system is more trustworthy (Mauk 2020). 13 For example, Sarah de Lange and Tjitske Akkerman (2012) showed that since 1997 both political trust and satisfaction with democracy have increased in Belgium with the emergence and consolidation of the Vlaams Belang populist party. Others, in turn, have concluded that populism fuels, instead of reducing, political discontent by exposing its supporters to a message in which they criticize the elite (Bergh 2004;Rooduijn et al. 2016;Schumacher and Rooduijn 2013;van der Brug 2003), with no effects on voter turnout (Immerzeel and Pickup 2015).
However, the increase in political trust when populists are successful depends on the context: the phenomenon has been found to be more pronounced in those political systems characterized by low democratic quality, low government performance and corruption (Mauk 2020). Similarly, also the increase in citizens' electoral participation linked to populism in power has been found to be moderated by the party role (lower when in government vs in opposition) and ideology (with right-wing populists surprisingly linked to a higher effect). Finally, the domestic political culture also plays a role in this aspect: some studies comparing various European democracies showed that it is only in Central and Eastern European countries that there is a significant 'participatory effect', especially in young voters (Leininger and Meijers 2020).
Broadly speaking, it must be underlined that studying the effect of populism in power on citizens' attitudes, values and behaviour poses serious challenges to researchers, since it requires the collection of longitudinal data, modelling the attitudinal consequences of (right-or left-wing) success over time (e.g. problems of causality etc.).

Some analytical guidelines for the study of the consequences of populism in power
With the reviewed literature in mind, there are three general arguments of interest for this special issue: first, it is not populism per se but populism in government that can be at odds with (liberal) democracy (see also Mudde and Rovira Kaltwasser 2012). Put differently, when in opposition, populist actors may hold attitudes that are highly critical of liberal democracy, but their mere existence may reveal positive effects in the realm of participation and representation. Second, once in government, populists unfold 'illiberal' effects on several levels. For example, right-wing populists may undermine minority rights in policy terms. At the same time, they undermine the polity by bypassing institutional checks and balances. Finally, potential moderating factors (i.e. democratic consolidation) may be in place: the more consolidated the democracy is, the more it will 'resist' substantial alteration of its nature.
In this respect, we suggest that populism in power should be studied not only by analytically disentagling the consequences in several domains (at least three, as pointed out in the previous sections), but also according to a multidimensional conceptualization of the effects, which can be simultaneously positive and negative; strong and weak; radical and moderated in the various domains. We argue that the investigation of the effects of populism in power should be unpacked in intensity (which can be absent/weak or strong), 14 direction (which can show a moderation vs a radicalization of the populist party in power) and content. This is in line with some recent typologies elaborated for the study of populism in power and health policies (Falkner and Plattner 2020).
In the contributions of this special issue a multidimensional conceptualization is applied to all three domains of the potential impact of populism in power and the assessment is made in both a quantitative and qualitative fashion. For example, Davide Vittori (2022), in his quantitative comparison of 19 countries in Europe, assesses the impact of populism in power on the quality of democracies, conceptualizing the impact according to 98 indicators of quality of democracy and three possible paths of outcomes, not necessarily mutually exclusive (as a threat, as a corrective, as a threat and a corrective). István Grajczjár et al. (2022) build 'typologies of solidarity', where the direction of attitudes towards solidarity and inclusion/ exclusion are combined with the intensity of the impact of populism in power on them across time, in the relatively long-lasting perspective which characterized the Hungarian case of populist ruling. Fred Paxton (2022) offers another view on how the policy influence of populism in power can be measured, pointing out 'differential consequences' experienced by local communities under populist governments. Finally, Jostein Askim et al. (2022), on the Norwegian case, show the importance of investigating the consequences of populist inclusion in government along not one, but several dimensions. While populist executive politicians can be similar to other executive politicians along some dimensions, on others they can differ to a greater extent.
This multifaceted conceptualization allows us to better understand more nuanced variations across cases and countries, as well as within cases in time. It may also suggest (through the possible combinations of intensity, direction and content) a set of preliminary mechanisms on different paths of populism in power across the three political domains such as: radicalization, compromise and moderation, splintering, or loss. All these types are exemplified in the case studies covered in the contributions to this special issuesuch as, for instance, radicalization in all the three political domains for the Hungarian case, which emerges as a paradigmatic case of populism 'grabbing power', determining institutional change and getting in full political control; or moderation in the Norwegian case (which, however, does not couple this with splintering as the Finnish populists did in power, just to mention another Nordic case).
Although this is an exploratory research effort, in this special issue we are also guided by some working hypotheses concerning the influencing or moderating factors of populism (Huber and Schimpf 2017;Juon and Bochsler 2020;Ruth 2018).
First, the debate on varieties of populism (left-wing or inclusionary vs rightwing or exclusionary) is taken into account to explain differences and similarities of the paths and impact of populism in the various domains. This approach considers the importance of the different ideological components of these parties (Ivaldi et al. 2017;Mudde 2016). 15 Our contributors explicitly or implicitly compare different types of populisms in power across three dimensions (Filc 2010;Mudde and Rovira Kaltwasser 2013): material (the distribution of resources among social groups), political (the appeal to forms of political mobilization that go beyond representative democratic channels) and symbolic (the boundaries of the notion of people). On all dimensions, inclusionary and exclusionary populist parties differ in the degree of 'inclusiveness' envisaged. In fact, different combinations of economic, political, societal and cultural factors have led to the manifestation of distinct varieties or 'subtypes' of populism (Caiani and Graziano 2019), with different ideological underpinnings, discourse and organizational features, which we expect may be reflected in distinct impacts on politics, polity and policies (e.g. in distinct policy proposals). However, there are also scholars who claim that radical left and right do not differ significantly in their populism (Rooduijn and Akkerman 2017).
Second, another important (explanatory) factor to be considered when analysing the consequences of populism in power is the institutional setting (i.e. presidential; semi-presidential vs parliamentary democracies, Kriesi 2018) within which they act, alongside the formal power that populist parties have in government (Biard et al. 2019)both aspects that we expect can influence degree and forms of their impact on several domains. In most European parliamentary democracies, the populists act within governmental coalitions which actually constrain their power (Albertazzi and McDonnell 2015). However, also in semi-presidential systems such as Poland, and in (quasi-)majoritarian parliamentary ones such as Hungary (to mention two cases investigated in this special issue), populist parties have the possibility of governing either alone or as the dominant political force in a coalition with junior partnersthat is, they might face less or no constraint in following their interpretation of democracy (Kriesi 2018). Not only the institutional framework of the country, but also the specific role of the populist actor within the government (leading or junior coalition partner of a majority or a minority government, or external supporter) may then affect the populists' chances of a successful realization of their governing goals. Likewise, the impact of government responsibility may depend on how long populist parties are in power and whether they have institutionalized (de Lange and Art 2011): generally new parties tend to be populist when they enter the party competition, but they tend to moderate their discourse as they age (Weber 2017).
Michael Minkenberg (2001) also points out the crucial role of party competition (i.e. the structure of party competition or systemic variables) in the various effects of populism. Finally, increasing academic attention focuses on the so-called political culture of countries, which can help or constrain the influence of populism in power: specificities among Eastern and Western Europe in the effects of populism are emphasized, determining effects which are context-specific and not easily generalizable (Leininger and Meijers 2020).
In this special issue we find a differential impact of populism in power depending on the type of populism at stake, the political domain and the institutional and organizational context (i.e. electoral strength of the populist party and governmental position) within which the populist parties act. Grajczjár et al. (2022) focus on individual-level explanations for attitudes towards solidarity or exclusion in times of populism in power, adding an extra layer of explanation ('the solidarity clusters') which mediate the relation between macro-level causes (i.e. the institutional setting of Orban in power) and macro-level effects (i.e. the changes in citizens' opinions and values). In her contribution, Michelle Falkenbach (2022), looking at an understudied level of government (the local one), demonstrates that parties matter: namely that the impact on health policy depends heavily on the populists' coalition partner(s) and the institutional constraints they face. Similarly, Eeelco Harteveld et al. (2022), in their study of right-wing populism in power, point out the relevance of moderating factors of polarization such as electoral success and government inclusion. Focusing on the inclusion-moderation hypothesis, Jasper Muis et al. (2022) show that populists in power affect 'protest voting'. They can endure in power as populists since they reduce political dissatisfaction among citizens.
Furthermore, specific hypotheses regarding the broader influencing or moderating factors illustrated above are elaborated in the various contributions (within an overall vein of theory refinement). For example, in his article Vittori (2022) stresses the role played by not only the duration of populism in power, as suggested by the extant literature, but also the numbers of years out of government, in the influence of populist parties once in power. Similarly, Askim et al. (2022) argue that the exceptionality of the Norwegian case is linked to the fact that populists in this context belong to a party (Norway's Progress Party) with a long history of parliamentary representation. Similarly, Kenneth Roberts (2022) adopts a historical comparison to account for the differential polarization effects of populism in power in different regions of the world (US, Europe and Latin America).
Finally, as we see in our contributions (although often implicitly), in most of the studies on the topic, the influence of populists coming into power can have reinforcing and interaction effects from one political domain to another (e.g. from the policies level to the level of influence on citizens' attitudes and values). However, so far, the various political domains potentially influenced (polity, policies and politics) are mainly explored in isolation and to our best knowledge no attempts at integrating them into a more comprehensive framework can be found in the literature.

The special issue
All the three spheres of populism's potential impact when in powerpolity, policies and politicsare examined. We bring together contributions that explore empirical manifestations of populists in power in several European countries, as well as key non-European cases such as the US and Latin America. Furthermore, the focus is on both left-wing and right-wing populism. Each contribution is a stand-alone article in which the author(s) selected one or more key elements of the analytical framework illustrated and applied it to the chosen countries. Specifically, considering this scholarly debate, our special issue aims to appraise the degree and varieties of populism's consequences, with regard to different populist parties and political spheres.
Starting with the polity dimension, using the Global State of Democracy (GSoD) dataset and relying on time-series analysis, Vittori (2022) assesses the impact of populism in government on the qualities of democracies. He conducts a comparison of 19 countries (from both Western and Eastern Europe) over three decades, trying to understand whether populist governments are more likely than non-populist ones to reduce the quality of democracy negatively. The results show a mixed picture: exclusionary populist parties tend to have more of a negative impact than other forms of populism; however, the role in government matters only to a limited extent. Grajczjár et al. (2022) investigate the Hungarian case and the regime change imposed by the populist government led by Viktor Orbán. Building on different types of data, including citizen surveys, in-depth interviews and secondary document analysis, the contribution argues that the main effect of populism has been the creation of a hybrid regime, conceptualized as a grey zone between democracies and autocracies. While democratic institutions in such regimes formally exist, their activities are greatly damaged and constrained. The contribution shows how disinformation, conspiracy theories and xenophobic media messages spread in public media and other government-friendly outlets, coupled with the government's isolationist politics, have helped this transformation, fostering moral panic and hysteria against refugees, NGOs and the Western world.
Moving to policies, Paxton (2022) investigates the consequences of populists in national government on policymaking in local government. Looking at electoral party programmes, leaders' speeches and newspaper coverage, the contribution focuses on two paradigmatic cases of local governments (Wels in Austria and Cascina in Italy) led by the populist radical right before and after the parties' entrance into national government. It sheds light on how the ideological impact of populist radical right parties in local government is highly conditional upon their simultaneous presence in national government and occupation of relevant ministries. The article offers another lens through which the policy influence of populism in power can be measured, allowing the understanding of differential consequences experienced by local communities under simultaneous local and national populist ruling governments. Still focusing on the subnational level, Falkenbach (2022) looks at healthcare policies. Using an in-depth case-study approach, her contribution analyses the health policy consequences of exclusionary populist parties in four Austrian and Italian regional governments over time. The findings indicate a propensity towards neoliberalism combined with accents of welfare chauvinism in Austria. In Italy, both regional cases mark a desire for welfare chauvinism but an inability to restrict healthcare access directly. The four subnational cases illustrate that the populist parties' impact on health policy depends heavily on their coalition partner(s) and on the existing institutional constraints.
With regard to the politics domain, by comparing three regions (Latin America, Europe and the US), Roberts (2022) looks at how (right-wing and left-wing) populisms divide the political arena between the people and the elite by politicizing economic or cultural issues often neglected by mainstream political parties, and may also transgress the conventional norms and procedures of established democratic regimes. He argues that polarization may be considered the most consistent effect of populismboth in its left-wing and right-wing variants -as it is integral to the logic of constructing populist subjects.
With an approach emphasizing the role of emotions in politics, Harteveld et al. (2022) examine the affective polarization brought about by populist radical right parties. Based on a comparative cross-country analysis covering 103 elections in 28 European countries and an examination of longitudinal data from the Netherlands, the findings show a strong correlation between the vote share of populist parties and the level of affective polarization at the aggregate level. Furthermore, the contributors show that at an individual level most populist parties' voters experience high levels of interparty hostility. The findings may have important implications for the process of coalition formation. Muis et al. (2022), using European Social Survey rounds  and multilevel regression analyses, explore how political power moderates 'protest voting' for far-right parties, problematizing the existing literature on why citizens vote for such parties (grievances related to socioeconomic deprivation, cultural opposition to progressive ideas, political disillusionment and protest against political elites). These findings point out that the notion of anti-elite populism is contextdependent and has a limited explanatory power for the understanding the rise of leaders such as Trump, Le Pen and Orbán.
Finally, in their contribution focusing on Norway, Askim et al. (2022) investigate how government is affected by including populists in a governing coalition: are they tamed when they obtain power, or do they maintain their outsider sentiments? By using survey data from 282 ministerial advisers from three cabinets in Norway, the study shows that when governing, populists are normalized on some governance dimensions and remain exceptional on others. On the one hand, they show professional experience, adhere to collegial decision-making and are politically responsive, on a par with the non-populists. On the other hand, populists differ from nonpopulist politicians in their contact patterns and their communication concerns.

Conclusion
This contribution provides an overview of existing research on the effects of populism on polity, policies and politics. It also suggests a number of ideas on how to think more systematically about the possible implications of populism coming into power, looking at the type of populism (and its material and cognitive resources), the institutional settings and cultural opportunities, the relation of populists with the other actors of the political system, as well as their framing of the social and political reality. We explore some of these ideas, focusing primarily on the European context, but also drawing on wider international literatures and empirical cases.
The special issue and this introduction aim to speak to the current body of research in this critical area of investigation and to push the research agenda forward, suggesting that more attention should be paid to the local level, to investigating comparatively subtypes of populism or to elaborating hypotheses about the possible linkages and interactive effects among the three spheres of influence (polity, politics and policies). Many questions are answered, while others are raised: What factors influence the outcomes of populism? Is it the 'populist' feature of these parties, the ideological imprint to which they are anchored or the mere passing of time (as an analytical factor; for insights from social movement studies, see Gillan and Edwards 2020)? And what are the moderating effects of the inclusion of populism in government?
These are still major lacunae of most studies on populist (mainly radical right-wing) parties in the European context. While the special issue and the contributions are not in a position to make any causal inference on what drives the political consequences, they offer empirical added value to a promising strand of research. Since the empirical reality in Europe limits researchers to a very biased set of populist parties with only a few left-wing or centrist (as in Eastern European cases) exceptions, this analytical introductory article as well as the contributions of the special issue help to widen the scope of the analysis of populism.
We did not manage to include one relevant issue which may play a substantial role in future consequences of populism in power: COVID-19. In the near future, the pandemic will also need to be considered, and conceptualized, when looking at the consequences of populism's success. Michael Bayerlein et al. (2021) have made an early attempt to understand the impact of populist governments on COVID-19 containment policies, suggesting that they have adopted less strict containment rules. In this respect, future research should investigate how COVID-19 has impacted on populist political leaders' communication and action, monitoring the evolution in terms of topics, features and sentiments. During the public health crisis, populist leaders across the world have often opposed the scientific community's suggestions on how to deal with the emergency, and, in some cases, have exploited the situation to reinforce their populist appeal in even more radical directions (accusing minorities, reducing democratic transparency and accountability, demobilizing protest: see della Porta 2020), and this may have an influence on the overall impact of populist parties on political systems, especially in those countries where they share a considerable amount of power. What the pandemic has revealed is that the impact of populists in power is not only a matter of possible general concern for democratic performance: populist political parties may be in government when decisive government action is of vital importance. hybrid and more recently technocratic populisms with its support for the Draghi government), although in a gradual way (Biancalana 2020). 9 Once in government, populists would mobilize emotions such as anger and hate against elites and other minorities in order to reproduce themselves, fostering polarization (Wirz 2018). 10 For example, welfare retrenchment or maintenance vs expansion; universalism vs deserving/undeserving groups; less deregulatory policies vs more; see Afonso and Papadopoulos 2015. 11 On the economic consequences of populism, see Rodrik (2018). 12 It must be underlined, however, that large-N studies have rarely been conducted on this issue. For example, by distinguishing between integration and immigration policies, Lutz (2018), in a comparative study on 27 countries, underlines that in radical right populist parties' mainly indirect policy influence is not generalizable across time and space. 13 In some cases, also improving trust for public institutions and democracy (Handlin and Collier 2008). 14 For example, in studies concerning the consequences of populism on welfare: Are welfare policies salient in their programmatic discourse? Do they adopt during their governmental experience (many) welfare policy initiatives? 15 Whereas left-wing populism identifies the people in socioeconomic terms, such as the working class, right-wing populism refers to the ethnic nation (Abts and Rummens 2007).