Political Oppositions in Democratic and Authoritarian Regimes: A State-of-the-Field(s) Review

Abstract Political opposition has long been one of the most dramatically understudied elements of real-world politics in contemporary democratic and authoritarian regimes. The past decade or so has, however, witnessed an upsurge of new opposition research that begs for a major state-of-the-field review. Interestingly, recent scholarship has focused more on manifestations of opposition in authoritarian and hybrid than in democratic systems, which indicates a latent reconceptualization of political opposition (setting aside older distinctions between regime-loyal opposition and regime-challenging forms of resistance, dissidence and contestation). With a focus on party-based forms of opposition, which have been widely considered to mark the most effective form of opposition, this review article takes stock and highlights key issues for future research as well as some inherent obstacles to the emergence of a more integrated field of cross-regime opposition studies.

For all the passionate commitment of contemporary democratic theory to considering political opposition a quintessential element of democracy, there is an inherent bias in both politics and the study of politics towards government, or more specifically the political executive, at the expense of political oppositions. 1 This is true for most of the past (spanning the long centuries of the pre-democratic age with its often spectacular manifestations of largely unfettered executive power), but barely less so for the present. Various dynamics have come to advance an executive-centred view of politics, and executive-centred research agendas in political science. Personalization, internationalization (including the rise of international summitry), an increased demand for centralized coordination at the core executive, as well as protracted political, economic and other crises (including the coronavirus pandemic) all have worked to focus public and scholarly attention increasingly onto the political executive, rather than its challengers (Andeweg et al. 2020). 2 The impression of an uneven playing field of governments and oppositions even in the most advanced democracies includes a striking lack of attention of mainstream political research and leading reference works to the political opposition. For example, the major Oxford Handbook of Legislative Politics (Martin et al. 2014) does not feature a single chapter on parliamentary/legislative opposition and even fails to mention the opposition in its subject index. Similarly, while it has been widely acknowledged ever since Giovanni Sartori (1976) that the very nature of a party system depends to a large extent on the core features of the opposition parties, many key contributions to the party systems literature, even those that prominently refer to Sartori's classic study, have curiously ignored the opposition (see e.g. Dalton 2008). At the level of book-length monographs of the past decade on political parties, the subject of political opposition has been marked by a heavy Westminster bias, with most contributions in this vein looking at individual parties when in opposition (see e.g. Begley 2020; Diamond 2021; Lavelle 2017) rather than into oppositional politics more generally. In most of this work, 'opposition' is reduced to little more than a contextual variable of party development. 3 Also, and no less importantly, much of this work is of a conspicuously non-comparative nature. At the same time, there is a burgeoningyet widely scatteredinternational literature on a wealth of different issues of political opposition in different types of political regime, which has become difficult to follow even for expert scholars. 4 Thus, it is about time to revisit 'the other side', once powerfully brought to the world stage of political science by Robert Dahl (1966a).
To keep the agenda of this article to manageable proportions, I shall focus on party-based forms of political opposition. As Dahl has contended powerfully, 'a political party is the most visible manifestation and surely one of the most effective forms of oppositions in a democratic country' (Dahl 1966b: 333). This is as true today as it was half a century ago. What is more subject to debate is the implied nexus between the existence of an opposition party and the democratic nature of a regime. While Dahl was right to emphasize that the absence of an opposition party could be seen as compelling evidence for the absence of democracy (see also Van Biezen and Wallace 2013: 292), the rise of electoral autocracy as the now most common form of contemporary authoritarian regime (Schedler 2013) has rendered the reverse argumenttaking the existence of an opposition party as evidence for a democratic orderless tenable than ever.
This obviously prompts the question of how to conceptualize an opposition party. In this article, we opt for an 'inclusive' understandingone that includes 'anti-system parties' (Capoccia 2002;Sartori 1966;Zulianello 2018), 'anti-elitist parties' (Otjes and Louwerse 2021), 'new challenger parties' (De Giorgi et al. 2021) and 'pariah parties' (Moffitt 2022) that are not part of the government of the day. This reaches beyond older notions that considered genuine opposition parties to be only those that other parties perceived as able and willing to participate in the alternation game of party government regimes (i.e. excluding 'anti-system parties'). Both the more recent conceptual debate about 'anti-system parties' and the changing features of these parties in real-world politics (Zulianello 2018) justify a more encompassing understanding of opposition parties as all 'non-governing parties'. More importantly still, such a wide, and somewhat simplifying, understanding of opposition parties as 'parties not in power' has governed recent research on party-political oppositions in different types of regime, including dictatorships. While this is to be acknowledged here as a useful starting point for a cross-regime state-of-the-field review, conceptual ambiguities are to be revisited in the closing section of this article.
In an attempt to capture the current state of the larger fieldwhich is marked by an established separation and widespread mutual ignorance of scholars working on democracies and non-democraciesthis review is organized into two major parts looking into recent research on political oppositions in democratic and autocratic regimes one after another. The key focus is on contributions from the past decade that have been published in the major English-language general and specialist political science journals, and chapters and books by major academic publishers. 5 The third part then offers a discussion that considers the prospects for a closer integration of these subfields.

Party-based political opposition in representative democracies
While until the close of the past century, even in many democracies from beyond the Westminster family, a main opposition party could be identified with ease, capturing the internal structure of the 'opposition' in many contemporary democracies has become a major challenge. In many countries, the 'opposition' now includes quite a few parties enjoying parliamentary representation, and a growing number of extra-parliamentary parties (see Best 2013). As some of those extraparliamentary opposition parties enjoy sizeable electoral support and/or other resources, this development has fuelled new research with a focus on the impact that extra-parliamentary opposition parties have on other parties in parliament or the government (see e.g. Franzmann 2019; Goldstein 2021). Research by Ko Maeda on 18 parliamentary democracies suggests that the levels of opposition fragmentation in parliament, and opposition parties' approaches to cooperation with other opposition parties, are to a considerable extent shaped by the rules of procedure in place. 'Deliberative parliamentary rules that allow opposition parties to have greater influence in the policymaking process lead to higher levels of opposition fragmentation', while 'opposition parties deprived of political influence tend to reduce their levels of fragmentation in order to become more competitive' (Maeda 2015: 763). Related research shows that opposition fragmentation is not just an important dependent variable worth studying but also a major factor shaping different dimensions of democratic governance, if in an ambivalent way. According to a study on the European integration process in ten Central and East European democracies, 'fragmented oppositions appear to diminish not only political competition, but may also undermine popular support for democracy' (Meka 2021: 17-18). At the same time, opposition fragmentation can enhance accountability, as a study making use of a survey experiment run in Spain early in 2020 concludes (Ferrer 2021).

Institutions
There is an established institutional bias in political research on party-based forms of opposition towards parliamentary democracies that has also marked the more recent chapters of international research in this field (see Helms 2016;Ilonszki and De Giorgi 2018). Classic approaches to studying parliamentary processes have been applied to analysing the parliamentary behaviour of new types of party. For example, in a recent study by Elisabetta De Giorgi et al. on new challenger parties, the 'formal rules and practices that determine the prevailing origin of the introduced legislation and MPs' activity patterns' are being identified as a key factor shaping profiles of parliamentary opposition (De Giorgi et al. 2021: 12). A more particular hallmark of a new generation of opposition studies has been the construction of major indices developed from observed institutional patterns in the established parliamentary democracies. These have included an 'opposition power index' (Garritzmann 2017), a 'policy-making power index of opposition players' (Wegmann 2020) and an index of different parliamentary questioning regimes (Serban 2020). Such studies are important, as most observable patterns of oppositional agency and government-opposition relationsbeyond the more particular question of opposition fragmentation or coherencerelate to the prevailing institutional opportunity structures.
In some contexts, institutional incentives and constraints can turn the parliamentary behaviour of opposition parties largely into a ritualarguably nowhere more so than at Westminster (see Dewan and Spirling 2011). The institutional imperatives of Westminster systems also tend to shape other intra-party dynamics of opposition parties operating under this type of regime, such as, and in particular, the politics of leadership turnover (So 2018). There is also some important work that looks into the role of formal and informal institutions in the historical evolution of the more notable organizational features of the political opposition, such as the historical emergence of the 'shadow cabinet' in the British context (Eggers and Spirling 2018). Even at Westminster, however, institutions shape much but, ultimately, determine little: opposition parties use legislative tools strategically to hit governments where it may hurt the most, which includes directing questions towards policy areas that uncover intra-coalition tensions (Whitaker and Martin 2021).
The most complex patterns of government-opposition relations tend to exist in multilevel contexts in which parties performing the role of opposition at the national level can simultaneously be in power at the subnational level of the same polity. The federal systems of Canada and Germany mark two exemplary cases of such substantially more complex configurations between government and opposition parties (see Auel 2014;Hohendorf et al. 2021;Smith 2013). The closer the institutional integration between the intergovernmental arenas, the more room there is for scholarly debates about the role of parties, and the nature of political opposition, in such 'compound regimes'. While some scholars have tended towards considering the federal power-sharing arrangements as a threat to the smooth operating of party competition and democracy, others have assessed the parties as actors undermining the beneficial effects of federalism (see e.g. Benz and Sonnicksen 2017). However, whatever the theoretical perspective, there is no denying that federalist institutions are likely to introduce a major element of negotiation between governments and oppositions, as on many occasions a certain amount of cooperation and consensus is needed to move things forward. 6 Ideology, size, experience, age and time There are other factorsbeyond institutional devices and arrangementswhose effects have been identified across institutionally stable contexts. As a comparative case study on the Netherlands and Sweden suggests, both the government's ideological composition and the status of the cabinet (including the history of cabinet formation) tend to have major effects on government and opposition voting in parliament (Louwerse et al. 2017). Specifically, 'the likelihood that opposition parties are ideologically similar to the government is lower during more extreme cabinets, leading to a lower possibility of compromise over policy between government and opposition' (Louwerse et al. 2017: 753), and ideologically extreme cabinets on their part are significantly more likely to emerge from wholesale alternations (Louwerse et al. 2017: 756). As Elisabetta De Giorgi and Francesco Marangoni (2015) show in a case study on Italy, the preferences and ideological stances of opposition parties affect the level of consensus on the passage of government legislation in parliament too.
Further, there are some more particular features of opposition parties, such as size and former experience in government, that tend to increase their chances of winning office in future elections, and thus lead those parties to pursue more confrontational strategies, as a comparative study across 16 national parliaments suggests (Tuttnauer 2018). Other recent research also points to the independent effects of the age of opposition parties, or more specifically their historical track record as opposition players in parliament. A case study on Germany suggests that, ceteris paribus, the older an opposition party (in terms of parliamentary representation), the more likely it is to engage in cooperative, rather than adversary, strategies (Hohendorf et al. 2020). By becoming established members of the club, 'ageing' opposition parties tend to lose their character as political enfants terribles and successively de-radicalize (usually in terms of both policy and style). Similarly, research on opposition parties' dealing with the coronavirus, and the government's coronavirus policies, at the level of parliamentary debates in four countries (Israel, Germany, the Netherlands and the UK), found that 'larger opposition parties with considerable prior government experience were more positive than larger parties without such experience' (Louwerse et al. : 1025. There is also important new evidence that 'time' is a factor of independent weight in shaping opposition behaviour. A study of six established democracies by Jan Schwalbach (2021) demonstrates that parties adapt their behaviour throughout the legislative term. While 'opposition parties do not become generally more negative towards the end of the cycle, … the effect of time on opposition parties is particularly determined by whether they can exert more influence on government proposals' (Schwalbach 2021: 15). A case study on minority governments in Sweden reveals that parties generally supporting a given minority government are less likely to do so towards the beginning and the end of the election cycle (Müller and König 2021). Time, or timing for that matter, is also at the centre of other strings of opposition research, such as in Laron Williams's article on the timing of successful no-confidence motions of opposition parties, which offers both a formal and an empirical model (Williams 2016). A series of articles by Petra Schleiter and Margit Tavits (2016), Petra Schleiter and Valerie Belu (2018) and Tristin Beckman and Petra Schleiter (2020), with empirical evidence from up to 27 Western and Eastern European countries, suggest that there are tangible benefits for governments controlling the electoral schedule and being able to call an early election at their choosing. However, this does not imply that the state of the opposition is of no relevance when it comes to 'snap elections'. Indeed, recent research suggests that the status of 'opposition preparedness' marks a major factor in its own right (McClean 2021).
Democratic party-political opposition beyond parliamentary systems As the sections above suggest, recent research on party-political opposition in different representative democracies has focused virtually exclusively on parliamentary systems, including some semi-presidential democracies which, by definition, share the 'fusion of power' element at the heart of executive-legislative relations with pure parliamentary democracies. Indeed, while David J. Samuels and Matthew S. Shugart famously contended that 'semi-presidentialism is more presidential than parliamentary' (Samuels and Shugart 2010: 255), this is much less, if at all, true for the patterns and policies of party-political opposition in those regimes than for chief executive-party relations or intra-party politics in the president's party.
There are crucially important institutional reasons for the apparent limits of systematic, party-based parliamentary opposition in presidential systems. Unlike parliamentary systems, which allow a majority of MPs to oust the government any time by launching a no-confidence vote, presidential systems do not provide any particular institutional incentive for legislators belonging to the same party to stick together at any cost. Still, interparty polarization is a factor that can create advanced levels of intra-party cohesion even in the absence of other institutional incentives. This is certainly true for the US, which has experienced a dramatic upsurge of polarization more recently, with polarized and polarizing patterns of behaviour extending well beyond the legislative arena (Russell 2021). The more particular notion, and study, of 'party opposition' in the US Congress, however, dates back at least half a century (see Patterson 1972). Meanwhile, soaring levels of polarization between the two parties in Congress have become such an established feature of US politics that scholarly inquiries into the nature of congressional lawmaking are increasingly committed to identifying the remaining amount of bipartyism (see e.g. Curry and Lee 2019). Another recent study on the US found that partisan efforts in the legislative process are shaped by the amount of party support a candidate received during the primary election. 'Members of Congress with more electoral support from the party are more likely to vote in line with their party's policy agenda' (Ballard and Hassell 2021: 10), which suggests that there are major determinants beyond the type of government shaping the nature of legislative politics, and possibly giving rise to distinct majority-minority patterns in the legislative arena of presidential systems. Still, there continues to be very little recent research on the more particular subject of party-political opposition in the US and other presidential democracies. However, the published work available suggests that it might be very rewarding to invest more resources into unravelling the manifestations of party-political opposition under presidentialism, including the fundamentally different ways of individual administrations to dealing with opposition parties (see e.g. Ashindorbe 2022; Egar 2016; Lee and Magyar 2022;Mietzner 2016).
While there is ample room for future research in all areas highlighted above, some major gaps in the literature on party-political opposition in parliamentary democracies particularly stand out. The first one relates to the astonishing fact that valuable conceptual frameworks for analysis that would lend themselves to comparative analysis easily, such as work on British opposition leaders (Bale 2015;Heppell 2012), have been completely ignored by others. To some extent at least, this seems to reflect the changing culture of academic publishing. A widespread application of a particular framework to different countries and contexts has long been typical, especially of frameworks specifically designed for major edited volumes. As volumes following a country-by-country approach are slowly but surely going out of fashion, this source has been drying up. Authors of journal articles, however, are expected to devise their own conceptual framework, rather than merely applying established frameworks to new empirical material.
Second, while we know something about how the performance of opposition parties impacts on the tenures of governing parties (Ziegfeld and Tudor 2017), cabinet agenda-setting (Borghetto and Belchior 2020), the perceived performance of the government (Seeberg 2020a) and the success of political chief executives (McCaffrie 2012), there is a notable scarcity of work devoted to uncovering how exactly political oppositions shape the public policies that governments make. Some valuable exceptions can be found (e.g. De Giorgi and Marangoni 2015;Maeda 2016;Seeberg 2016Seeberg , 2020b but they have remained too patchy to generate anything coming close to a more systematic debate. In some countries, both opposition parties and parliaments are simply not particularly powerful policymaking actors; yet in others, there are complex formal and informal structures of 'co-governing' that cannot reasonably be ignored. Third, we need to know more about how the different arenas in which opposition parties operate, and the behavioural patterns observed in any of them, relate to each other. Some authors have questioned to what extent, if at all, patterns of party competition in the electoral arena are being reflected at the level of parliamentary decision-making. Rudy Andeweg (2013) identified a general trend towards collusion at the parliamentary level that contrasts starkly with the more competitive patterns observed in the electoral arena, and that could ultimately undermine the trust of voters in the very idea of representative democracy. Other authors as well have suggested that the connection between the issues that parties choose for waging electoral campaigns and the ones their representatives in parliament choose to address may be weakening in the course of many of the established democracies becoming evermore fragmented and personalized polities (Tuttnauer 2020: 212). As with any major thesis seeking to capture general evolutionary dynamics across a wider region, such assessments have been challenged in particular by single case studies (see e.g. Loxbo and Sjölin 2017). Various comparative assessments of the parliamentary performance of different parties suggest that many of the right-wing populist/anti-elitist opposition parties especially tend to stick to their adversarial style once in parliament (see e.g. Louwerse and Otjes 2019;Otjes and Louwerse 2021), and also many of them do not become more moderate even if they win governmental office (Schwörer 2022). Further, there has been more particular research demonstrating that Eurosceptic challenger parties in Sweden shaped the oppositional behaviour of mainstream parties, which comes as a blow to the waning-of-opposition thesis in EU affairs (Persson et al. 2022). Yet, for the time being, there is no up-to-date comparative empirical assessment of the waning-of-opposition thesis in sight.
Fourth, the more particular features of political opposition in semi-presidential democracies have remained strikingly understudied. While political opposition in semi-presidential democracies can look very similar to its counterpart in parliamentary democracies (see above), this is true only for periods of 'unified government'that is, control of the presidency and the assembly by the same party or group of parties. A different picture emerges, however, in times of split party control of parliament and the presidency (i.e. what the French refer to as cohabitation).
In that case, the president's party, while controlling the presidency, can still be the parliamentary opposition, and 'the opposition to the government is led by the president jointly with the assembly minority' (Shugart 2005: 323; see also Helms 2004: 38-39). In their major study, Samuels and Shugart managed to demonstrate that the more notable institutional features, or type, of semi-presidential system can make much of a difference with regard to the politics of opposition under semipresidentialism: 'When oppositions win an assembly majority in premier-presidential systems, the result is virtually always cohabitation. … In contrast, opposition majorities in president-parliamentary systems are extremely rare to begin with … and even in those situations, presidents can influence cabinet composition' (Samuels and Shugart 2010: 88). While this has been less of a conclusion than an invitation to look more closely into the complex patterns of political opposition in different subtypes of semi-presidentialism, this call has been ignored, even in works representing the 'third wave of semi-presidential studies' (Elgie 2016).
A fifth major gap concerns the relationship between political opposition parties represented in parliament and extra-parliamentary players, including other opposition parties currently not represented in parliament. The importance of considering the role of extra-parliamentary opposition players is increasingly acknowledged, even in the Westminster literature, which has traditionally focused virtually exclusively on oppositional politics in parliament (see Bailey 2014). There are certain institutional and political contexts that provide a particularly favourable breeding ground for coordinated actions between MPs and extra-parliamentary actors, such as the political system of the European Union, for which this relationship has been analysed in some detail (Crespy and Parks 2017). But understanding the relationship, or non-relationship, between parliamentary opposition parties and other opposition actors better is of major, and increasing, importance for all democratic regimes.
Last but not least, another glaring gap in the study of democratic political oppositions concerns the striking absence of a gender perspective. 7 While the political executive, once famously characterized as 'the most masculine' political area of all (Jalalzai 2008: 209), has long been conquered by feminist scholars around the world, there has been little if any research specifically devoted to women opposition leaders, or women and opposition politics more generally. Early wake-up calls from scholars working on contexts beyond the major established democracies (Vincent 2001) have been ignored for too long. We know something about gendered opposition to female politicians (Och 2020), and parliamentary opposition to gender equality more generally (Kantola and Lombardo 2020), but little to nothing on how female politicians have performed the role of opposition politicians, and what distinguishes them from their male counterparts. No less surprisingly, the few contributions to this field testify to the apparently irresistible allure of executive power. An important piece on Margaret Thatcher and Angela Merkel as opposition leaders (or, strictly speaking, on the ways women reach the top of their party) is curiously framed as a study on women leaders 'before prime minister' (Beckwith 2015) as if opposition leaders were not sufficiently important to be studied in their own right, even if they eventually may fail to win executive power. Related research on election pledge fulfilment in ten European countries, Canada and the US suggests that parties with a woman party leader are much more likely to fulfil their election promises (Homola 2021)a finding with immediate relevance also for parties desperate to win governmental power in the first place.

Party-based opposition in competitive autocracies
The second part of this article is devoted to party-based forms of opposition in regimes beyond the family of liberal democraciesan area rightly identified as largely uncharted territory just two decades ago (Franklin 2002). Meanwhile, there is an established tradition of looking into the politics of competitive authoritarian regimes through a party lens. Indeed, it is possible to identify the early sprouts of what could develop into a 'party turn' in democratization research, a novel focus on both ruling and opposition parties, and their complex interactions with each other (see Riedl et al. 2020). Importantly, the party factor is not something that has simply been 'read into' the contemporary politics of authoritarianism by a new generation of scholarship. Political parties have actually gained importance across different regimes beyond liberal democracy. In competitive autocracies that emerged from 'autocratized' liberal or electoral democracies (see Lührmann and Lindberg 2019), opposition parties were, as it were, inherited from those countries' more democratic periods, which obviously does not preclude the formation of genuinely new parties.
Elsewhere, parties (other than the party organizations of authoritarian powerholders themselves) emerged in the wake of the transformation of formerly closed autocracies into competitive autocracies with more or less regular elections. In those latter types of autocratic regimes, the decision to hold elections and to tolerate some opposition party activity is usually a well-calculated risk that autocrats take in order to help stabilize their hold on power (Geddes et al. 2018: ch. 6). As Erica Frantz and Andrea Kendall-Taylor note, 'by creating parties and a legislature, a dictator draws his potential opposition out of the general public and into state institutions, making it easier to identify who these opponents are, to monitor their activities, and to gauge the extent of their popular support' (Frantz and Kendall-Taylor 2014: 332). Recent research also suggests that decisions about the institutional features of the electoral system follow rational considerations and reflect the different capacities of autocratic rulers. 'Resource-rich dictators are incentivized to employ proportional representation systems to alleviate the threat from the masses and pre-empt the emergence of new opposition, while resource-poor dictators tend to choose majoritarian systems to co-opt ruling elites in the legislature' (Chang and Higashijima 2021).
The power-stabilizing effects of autocratic elections and opposition parties Autocrats have countless instruments at their disposal to give their would-be challengers a hard time and keep the opposition from becoming too powerful (see e.g. Morgenbesser 2020; Reny 2021; Yilmaz and Shipoli 2021). However, there is a heavy bias in autocracies towards the regime and incumbent parties, not just at the level of rules and resources (Arriola 2013; Rakner and Van de Walle 2009), but also at the level of voters. As Ora John Reuter (2021) contends in light of evidence from a Russian case study, 'regime supporters feel a bond with the state and, therefore, feel a much stronger duty to vote. This leads them to vote in large numbers. Opposition supporters, by contrast, feel alienated from the state and stay away from the polls' (Reuter 2021: 14).
What is more, opposition parties can stabilize an established authoritarian regime even further. This is especially the case when a regime manages to co-opt some opposition parties into the regime, creating a 'loyal opposition' and thus a division between 'insiders' and 'outsiders'. This phenomenon has been widespread, including regimes as different as Botswana, Egypt or Russia (Albrecht 2005;Armstrong et al. 2020;Selolwane 2002;Turovsky 2014). The patterns observed at this level primarily reflect the government's way of dealing with opposition parties (see Arriola et al. 2021) and the overall ability, or inability, of opposition parties to provide a credible alternative. However, party features mark a factor in their own right when it comes to explaining whether or not opposition party leaders accept co-option offers from autocratic rulers. Other things being equal, parties with a strong activist base and a unitary leadership are considerably less likely to acquiesce to the regime (Buckles 2019). This is largely confirmed by what marks the first cross-national party-level quantitative study of the relationship between internal characteristics of opposition parties and elite co-optation in electoral autocracies (Kavasoglu 2021). Regardless of the availability of patronage resources that can be distributed among opposition party leaders, 'organizationally extensive opposition parties, and those that distribute internal decision-making authority among various party members, are less likely to be co-opted' (Kavasoglu 2021: 16), and in particular if they are ideologically distant from autocratic incumbents. On a related note, party leadership (including party organization building) has also been identified as a key factor shaping the ability of the opposition to disrupt the stability of a dominant party system, and to appeal to new voters, instead of being absorbed by the regime (Mac Giollabhuí 2019).

Strategic choices of opposition parties
The central focus of much work in this field is on the strategic choices and behaviour of opposition parties in the electoral arena. Opposition parties in competitive autocracies have used fundamentally different strategies. To begin, cooperation and coalition building between opposition actors have increasingly become major topics in their own right. According to calculations by Jennifer Gandhi and Ora John Reuter (2013: 140), pre-electoral coalitions were formed in a quarter of all authoritarian elections held in the first decade of the twenty-first century (Gandhi and Reuter 2013: 140). Comparative research on electoral coalitions suggests that, other things being equal, the willingness of the opposition to form pre-electoral coalitions tends to increase when change seems likely, or at least possible (see Hauser 2019). Conversely, both state-sponsored electoral violence and strategies of collusion of 'loyal' opposition parties may undermine the opposition's efforts to build electoral alliances (Armstrong et al. 2020).
A recent study on opposition coordination in Venezuela suggests that decisionmaking and strategy formation are strongly shaped by the amount of repression opposition parties face from the regime. As Maryhen Jiménez contends, there is a 'curvilinear relationship' between different levels of repression and forms and degrees of opposition coordination. When levels of repression are either very high or very low, activities of opposition coordination tend to be limited, and forms of cooperation mostly informal or clandestine; by contrast, under medium strong repression, opposition parties are significantly more likely to coordinate systematically with each other (Jiménez 2021). Other important differences in the politics of opposition coordination uncovered by recent research relate to the background of the protagonists. Evidence from Morocco suggests that the observed increase in collaboration between the oppositional left and Islamist movements was motivated by 'the excluded nature of these actors and their lack of electoral interests' (Casani 2020(Casani : 1183). Yet, there seems to be no general advantage in drawing on 'excluded actors', or at least not at the level of opposition performance; on the contrary, case studies on the former Soviet Union suggest that coalitions that include previous regime insiders have often been more successful (Hauser 2019).
More than any other recent case of an opposition coalition-driven alternation of power, Malaysiawhere the Hope Alliance (Pakatan Harapan) ousted the previously hegemonic Barisan Nasional (BN) government in 2018has become a showcase for studies of the performance of opposition parties in authoritarian contexts. While Andreas Ufen argued convincingly that Pakatan Harapan was successful because it scored highly in terms of comprehensiveness, cohesiveness and linkage to voters and civil society networks (see Ufen 2020), the Malaysian experience still comes as a major challenge to virtually all assumptions governing the established 'opposition-split hypothesis'. Counter-factional election simulations by Kai Ostwald et al. suggested 'that the opposition split neither dramatically helped nor hurt the BN', implying that the established wisdom concerning opposition coordination 'manifests only when its assumptions accord with local realities' (Ostwald et al. 2018: 31). The case of Malaysia has also become an important resource for reconsidering the complex and possibly contradictory effects of repeated elections in authoritarian contexts. As Yukiko Taniguchi contends, 'while repeated elections curb regime changes by mass protests', which has long been the standard assumption in this field, they also 'promote opposition engagement in within-institutional politics and the formation of opposition coalitions' (Taniguchi 2020: 31-32). Further, as Jennifer Gandhi and Elvin Ong's Malaysian survey experiment suggests, 'one important source for the failure of opposition coalitions … stems from opposition voters themselves. Party leaders may anticipate supporters' hesitation to engage in cross-party voting and decide that the formation of a coalition is not worth the costly effort. Even when leaders successfully negotiate coalitions, not all of their supporters may be willing to follow them into the gamble' (Gandhi and Ong 2019: 961). As Ong demonstrates in a follow-up study on the 2018 Malaysian election campaign, the nature of campaigning activities is a factor of independent weightan opposition alliance's joint campaign was found to increase 'cross-party strategic voting' by about 10 percentage points among opposition voters (Ong 2021).
A fundamentally different election-related strategy of opposition parties, which has been notably widespread across Africa, concerns opposition boycotts. Most early work on boycotts concurred that opposition parties will boycott in particular when they expect to do poorly in an upcoming election. However, recent research suggests that things are much more complex, and that perceptions of regime strength and stability among opposition actors, including those that extend beyond immediate election-related considerations, play a major role in their own right (Buttorff 2019: 7). Related research has looked into the effects of opposition boycotts. In addition to more elusive losses of reputation, as Megan Hauser shows, boycotts tend to produce in particular lower turnout, which may become the bedrock of future criticisms and challenges of the regime (Hauser 2019: 21). Importantly, while organizing boycotts is, as suggested above, an election-related strategy of political oppositions in authoritarian regimes, it ultimately reaches beyond an electoral confrontation. As a case study on Ghana suggested, whatever strategies opposition parties operating under competitive autocracy and in emerging democracies may use with reasonable success (including forms of electoral clientelism), these previously successful strategies cannot simply be carried over to a post-transitional regime (Weghorst and Lindberg 2011). As voters' experience grows and expectations change, party strategies designed to secure continued electoral support have to change, too.
Election boycotts must be distinguished from parliamentary boycotts. The latter have been widespread even in regions, such as across the Western Balkans, where electoral boycotts have been uncommon, particularly among the larger opposition parties. Parliamentary boycotts, which tend to be temporary and easy to reverse, 'seek to deprive parliaments of their legitimacy and are usually combined with specific demands for either early elections or reforms' (Laštro and Bieber 2021: 624).
The recent 'institutional turn' in the comparative study of autocracies (Pepinsky 2014) has also come to shape research on political opposition in those regimes, and the choice of strategies more specifically. Interestingly, many authors have emphasized the 'empowering' features of some institutions rather than institutional constraints, which are obviously strong in all types of authoritarian regimes. In light of lessons from Colombia and Venezuela, Laura Gamboa (2017) suggests that, whenever the opposition enjoys some institutional resources, they are well advised to use them instead of relying exclusively on extra-constitutional strategies and means. In that vein, other authors argued that moderate responses to executive aggrandizement are a more effective means to keep autocracy at bay than irregular opposition attempts to oust incumbent power-wielders (Cleary and Öztürk 2020). Moreover, a case study on political opposition in Turkey contends that attempts by autocrat rulers to tighten their control by institutional means and further restrict the room for manoeuvre of the opposition parties may backfire, prompting the opposition to look for genuinely novel strategies to challenge the regime (Aras and Helms 2021). Very much in line with this argument, the leaders of six Turkish opposition parties actually gathered in early 2022 to hammer out a shared strategy designed to unseat the country's long-term ruler Erdogan (Washington Post 2022).
One of the most sophisticated recent contributions to the wider field is that by Murat Somer et al. (2021), which is devoted to the comparative study of opposition strategies in hybrid regimes suffering from 'pernicious' forms of polarization by diverse power-holders. The authors develop a typology of potential opposition goals, strategies and tools, and evaluate how these may affect polarization, and in turn democratic quality, from a time-sensitive perspective. Their theoretical framework links the choice of preservative versus generative ideological-programmatic goals and reactive versus proactive counter-polarization strategies with their expected impact on polarization dynamics. As the authors contend, neither passively avoiding polarization through withdrawal or elite cooperative mechanisms nor the pursuit of proactive counter-polarization strategies that seek to create a new pro-democratic axis are promising options for a democracy-minded opposition. Rather, it is 'proactive counter-polarization strategies [that] tackle the dominant axis of pernicious polarization head on, seeking to create a new pro-democratic axis in a transformative repolarizing strategy', or defusing the dominant axis 'by (re) creating cross-cutting ties in a plural polarization', which are identified as 'the most promising and democratizing strategies for opposition forces' fighting polarizationbased forms of autocratization (Somer et al. 2021: 943-944).

Opposition parties in authoritarian legislatures
The recent surge of research on authoritarian legislatures (see e.g. Gandhi et al. 2020;Opalo 2019;Schuler 2021;Shirikov 2021) has largely passed by issues of political opposition in the legislative arena. However, some authors have made important inroads into the study of government and opposition patterns. For example, a recent study by Emilia Simison looks into the legislative process in the Brazilian Congress during the last dictatorship . While the patterns observed do not amount to anything like a full-blown opposition mode in parliamentary democracies, Simison's findings clearly suggest that the government or opposition status of legislators matters, with pro-government and opposition legislators behaving differently, and focusing on different areas when introducing bills (Simison 2022). According to a study by Felix Wiebrecht (2021) which uses a large-N crosssectional research design , the existence of an opposition is conducive to more de jure and de facto powers of authoritarian legislatures; however, importantly, the oppositions' electoral strength is not linked to legislative strength. This echoes other research which suggests that small rather than big oppositions (among other factors) tend to favour parliamentary initiative and a legislative function of authoritarian parliaments. As Gerrit Krol concludes in his study on Eurasian autocracies, 'a large opposition results in less overall activity because it implies that a higher proportion of powerful seats are occupied by members without support from the loyalist majority' (Krol 2020: 248).
The more particular effects of the parliamentary opposition tend to depend to a large extent on the nature of a given regime. As a case study on the Muslim Brotherhood in Egypt reveals, the party benefited from its membership in the legislature, 'as it could either demonstrate policy influence or force the Mubarak government to act in an increasingly autocratic manner' (Loidolt andMecham 2016: 1017). However, as the same authors note, 'the benefits from these mechanisms are most likely to be realized when the regime is characterized by elected legislative assemblies in which a ruling party's dominance remains uncontested, but where the state is at least formally (if not in practice) bound by a set of rules that does not completely monopolize the electoral process or media coverage of legislative activities' (Loidolt andMecham 2016: 1017). This implies that what may work in semi-authoritarian or hybrid regimes may not work equally well under more advanced forms of authoritarian rule.

Major gaps
Some of the most conspicuous gaps in the literature on party-based political opposition in competitive autocracies display notable similarities to the state of the art of political research on democratic political oppositions. First off, there is a major shortage of comparative research applying the same analytical framework to a larger number of cases. Most studies that do so have a strong regional biasthat is, a focus on a sample of countries from the same region, an approach marked by several inherent limitations. There are, however, some recent contributionssuch as a study by Aris Trantidis (2022) on the contrasting performance of opposition parties in Belarus and Slovakia, or by Gabriella Ilonszki and Agnieszka Dudzińska (2021) on the political opposition in Poland and Hungarythat impressively demonstrate the special value of a theoretically informed case selection (in contrast to a simple regional focus). The findings of such work help us unpack puzzles and identify the factors that make a difference even in widely similar contexts. The key message from Trantidis (2022) and Ilonszki and Dudzińska (2021) is that, even in otherwise largely similar contexts, oppositional agency matters a lot when it comes to fighting autocratization dynamics more or less successfully. As an earlier study by David White (2011) on opposition party strategies in the hegemonic party systems of Russia, Mexico and Japan demonstrates, there is much to be learned also, and perhaps in particular, from comparative inquiries into systems that share some features, but not others.
Second, again in analogy to the state of the field of political oppositions under representative democracy, there is little if any research on opposition leaders, and a striking absence of research on women opposition leaders in authoritarian contexts. This gap is all the more deplorable, as some of the most notable episodes in the recent history of political opposition against authoritarian rule (in Belarus and elsewhere) have been marked by the prominent involvement of women leaders (see, however, note 7).
Third, the evolution of electoral support for different opposition parties would seem to be an issue well worth considering in its own right. Specifically, why a sizeable share of supporters of an opposition party continues to support that party after it has been co-opted by the regime remains one of the major puzzles in this area. There has been some valuable theoretical modelling (Kosterina 2017), but very little empirical research to date. This is only one of the elements of authoritarian party system persistence and change, whose particular dynamics have been captured in a littlenoticed article by Grigorii Golosov (2013). Most other features identified by Golosov have maintained their importance for the working and scholarly understanding of authoritarian rule too, and should be confronted with new empirical developments.
Fourth, political oppositioneven, or perhaps particularly, in authoritarian contextsis not an end in itself. One of the many lessons of the much-studied Malaysian case is that even the most spectacular electoral victories of opposition parties may be short-lived. While the fate of Malaysia's opposition in the aftermath of the 2018 election has been assessed by several authors (see e.g. Lemière 2021; Ong 2021), much more systematic, and comparative, inquiry is needed to understand the conditions of turning electoral victory and alternation into a more durable new regime. A study by Michael Wahman (2014) on three African states, which looks at opposition victories as 'an independent variable that, under certain circumstances, could promote democratization' (emphasis added), continues to set the standard in this area.
Finally, the relations between opposition parties and other societal actors deserve considerably more attention than they have received in the past. The seminal study by Valerie Bunce and Sharon Wolchik (2011) on democratization in postcommunist central Europe provided convincing evidence that successful opposition parties could draw on the sustained support of both local and international civil society actors. The major volume by Nancy Bermeo and Deborah Yashar (2016), which conceptualizes opposition parties and social movements in developing countries as 'pivotal collectivities', has powerfully set the scene for more research in this vein, yet to date this passionate call has not been heeded. Whenever the community resumes work on this aspect, it should prove beneficial also to take into account the findings from studies of deviant cases in which opposition party development succeeded even in the absence of local elites and civil associations (Paget 2019).
Where to from here? More than half a century after the publication of Dahl's seminal volume on Political Oppositions in Western Democracies (Dahl 1966a) political research on oppositions has come to encompass a much wider sample of regions and regimes. Indeed, contemporary research on political oppositions in autocratic or autocratizing regimes is on, if not above, a par with that on political oppositions in established democracies. The sections above offered a stocktaking exercise that consciously sought to respect the distinct boundaries of two subfields that have evolved largely in isolation from each other. That said, there is something that most political oppositions in democratic and autocratic contexts share with each other, and which could seem to make them complementary subjects of future political research: being out of power, and the conviction that the political and policy status quo can be, and should be, changed through individual and collective action (Helms 2021: 569). These shared features might indeed become the starting point for further comparative inquiry. However, as the concluding considerations below suggest, there is no easy way forward.
Notwithstanding the strong allure of any closer cooperation, and the possible emergence of a new discipline, 'Comparative Political Opposition', there is some good reason to argue that scholars on both sides of the aisle have studied phenomena that are disparate and distinct, and are likely to remain so for the foreseeable future. Apart from very basic notions, such as those sketched out above, differences abound. Defining features of democratic governance include, in particular, the freedom of expression and a set of democratic rules of the game, a fully legitimate status of the political opposition, and their realistic prospect of becoming the next government within the systemic settings of that very regimefeatures that are conspicuously absent in most contexts beyond liberal democracy. This inevitably shapes the nature of political opposition in electoral autocracies. Ultimately, as 'multiparty elections in autocracies are partially free but unfair, opposition parties are compelled to compete for office while contesting the rules of competition' (Trejo 2014: 332). 8 The prospects for the emergence of any shared agenda are therefore less than rosy. A major problem concerns issues of terminological ambiguity. Some widely used terms, such as 'anti-system party', have fundamentally differentin fact virtually oppositemeanings, depending on context (see Helms 2021: 570). For this reason, they cannot easily become the vocabulary of any closely integrated research paradigm. More generally, many comparisons of opposition-related phenomena in democratic and authoritarian contexts would come at the risk of serious forms of 'conceptual stretching', including the complete ignorance of the distinction between the concepts of opposition and resistance, as can be found in the history of political thought (Helms 2021: 570-571). Last but not least, studying political oppositions operating under fundamentally different conditions within a shared framework would involuntarily have a delicate political dimension: a de facto acknowledgement that 'genuine' political opposition is possible even where its fundamental prerequisites are missing, which could be easily taken as a suggestion that many authoritarian regimes and their rulers are more democratic than is widely perceived.
This does not imply, however, that scholars with different core agendas could not learn a lot from each other and provide mutual inspiration across the aisle. For example, the recent suggestion by  to reach beyond defining opposition performance in terms of policymaking and scrutiny, and look into the 'opposition's general performance and their political system-related behaviour' (Ilonszki et al. 2021: 722) should have major inspirational potential across the wider community of opposition scholars. Additional support for the pursuit of such an agenda comes from related research, which suggests that voters do hold opposition parties accountable for the state of affairs in their country, if to a lesser degree than incumbent parties (Stiers 2022). Further, many issues relating to the politics of opposition are immediately relevant for different types of regime. Take, for example, personalization or polarization, which have figured prominently in both contemporary democratic and authoritarian politics, and the political study thereof (see e.g. Arbatli and Rosenberg 2021;Frantz et al. 2021;McCoy and Somer 2019;Muirhead and Rosenblum 2020). The realization that personalization and polarization may take rather different forms in democratic and authoritarian settings, and affect political oppositions in categorically different ways, could well become the source of a deeper understanding of key issues on either subdiscipline's agenda.
Notes as a whole, rather than parliamentary minorities. Further, even a full-scale assessment of parliament-based forms of opposition would not amount to a complete picture, as many party-based forms of opposition are of an extra-parliamentary nature, and there is a wealth of other forms and means of challenging and contesting governments and their policies. 2 Recent research on four Mediterranean countries suggests that some political crises may actually generate an advantage for opposition parties, at least in terms of their capacity to maintain programmatic coherence (Conti et al. 2019), yet this does not change the larger picture much.
3 Which testifies to the wisdom that a period in opposition tends to mark a particularly favourable opportunity for large-scale party reform (see Gauja 2017). 4 For previous stocktaking exercises, see Brack andWeinblum (2011), Helms (2008) and Norton (2008). 5 Democratization, Government and Opposition, and Party Politics clearly stand out as the international hub of contemporary political opposition research, with more than ten articles specifically addressing opposition issues each published in the past decade. Most major general journals, such as the British Journal of Political Science or the American Political Science Review, have had at least one or several contributions on political oppositions in the past decade, while others, such as European Political Science, published a symposium/special section on political oppositions recently. There has been, however, neither a book series devoted to issues of political opposition nor any major reference work in that area as yet. The sample of countries emerging from this review (more or less) mirrors the regional bias marking the recent international literature. For example, the omission of party-political opposition in Latin America reflects the conspicuously limited regard that scholars have shown for government-opposition relations in this region. There has been very little opposition party research (published in English) since the seminal article by Morgenstern et al. (2008), though some exceptions can be identified (see e.g. Arguelhes and Proença Süssekind 2018;González 2021;Jones et al. 2009;Madrid 2019;Tarouco 2017). 6 A particular complexity of government-opposition relations is, however, not a feature of genuine federations only. As Nicola McEwen et al. (2012) have rightly argued, the 'diffusive features' of political opposition in multilevel systems can be observed in decentralized unitary states such as the UK as well. Furthermore, both government formats and in particular patterns of party competition (i.e. congruence or incongruence, and the degree of incongruence) tend to have a major impact on the scope and the nature of political opposition in such regimes (McEwen et al. 2012: 189-192). 7 See, however, the forthcoming special issue of Politics and Governance on women opposition leaders in different types of regime (Helms et al. 2023). 8 As Eloïse Bertrand argues, this may not necessarily paralyse the opposition: 'protest and participation can be complementary and an effective way to challenge the regime' (Bertrand 2021: 610). However, this does not change the fact that the nature of this double strategy is fundamentally at odds with the situation in which mainstream opposition parties operating in established representative democracies find themselves.