Political Polarisation

Political polarisation is increasingly recognised as a critical challenge for democratic governance. It shapes how citizens interpret facts, deepens distrust in institutions, and weakens electoral accountability – core ingredients not only for democratic legitimacy, but also for effective policymaking, service delivery, and social cohesion. While polarisation is often studied in the context of high-income democracies, its consequences may be even more severe in low- and middle-income countries, where institutional safeguards are weaker, media systems are more fragmented, and identity-based politics are more entrenched. In these settings, polarisation isn’t just a threat to political competition – it can undermine development by weakening accountability, trust, and service delivery.

These are not isolated cases. Political polarisation has risen sharply across most regions over the past two decades. While most empirical research has focused on advanced democracies, data from the Varieties of Democracy (V-Dem) project shows that polarisation is increasing across nearly every region – not just in the US and Europe, but also in sub-Saharan Africa, Latin America, and South and Southeast Asia (Figure 1). This pattern holds both for elite rhetoric and mass attitudes, with growing divergence among political actors and declining trust across partisan lines.

Figure 1. Political Polarisation is Rising Across the World

Source: Regional averages of political polarisation from V-Dem (Coppedge et al. 2024) (Larreguy and Raffler 2025).

Much of the empirical research on polarisation remains concentrated in advanced democracies, where rich data on voting, party platforms, and congressional behaviour is available (e.g. Gentzkow et al. 2019, Draca and Schwarz 2024). However, a growing number of studies are beginning to explore polarisation in more fluid political systems, including emerging democracies where party systems are weak, institutions are less consolidated, and identity politics are more salient. These contributions are critical for understanding how polarisation operates across contexts, and for building policy-relevant strategies to mitigate its effects.

Understanding polarisation is essential for scholars and policymakers working in development. In polarised settings, voters are more likely to view information through partisan lenses, reducing the effectiveness of transparency campaigns and performance audits, as well as the incentives for improving policymaking and service delivery. Elite actors, in turn, may face stronger incentives to deploy divisive rhetoric – especially where checks on executive power are limited. Section 3 reviews this evidence, with special attention to how these risks vary across institutional environments.

What drives polarisation? A large and growing literature identifies multiple reinforcing mechanisms, including social identity, institutional incentives, elite behaviour, and traditional and digital media. In some cases, polarisation reflects genuine conflict over values or policy preferences. In others, it is deliberately stoked by political actors seeking to mobilise support, distract from performance failures, or delegitimise opponents. Online and social media have amplified these dynamics by fuelling ideological segregation, promoting affective hostility between groups, and enabling echo chambers and algorithmic amplification. Section 4 explores these mechanisms, drawing on comparative evidence across regions.

While much of the early scholarship on polarisation emerged from the study of advanced democracies, recent research increasingly examines its causes and consequences in low- and middle-income settings. The global evidence base has expanded to exploring polarisation in fragmented information environments in less-institutionalised contexts. This VoxDevLit brings together work from economics, political science, and other disciplines to synthesise what we know about the rise of polarisation, its downstream effects on development, and the effectiveness of interventions designed to reduce it.

The VoxDevLit proceeds as follows. Section 2 defines core terms, distinguishing between ideological, issue-based, and affective polarisation, and polarisation among voters, elites, and the media. Section 3 reviews how polarisation contributes to democratic backsliding, weakened accountability, and policy uncertainty. Section 4 examines key drivers of polarisation, from social identity and elite strategy to media systems and algorithmic amplification. Section 5 synthesises evidence on interventions to mitigate polarisation, including social contact programmes, elite messaging, institutional reforms, and information-focused strategies. Throughout, we draw on findings from diverse empirical contexts, with special attention to implications for development and governance in low- and middle-income countries.

For full reference list see the end of the conclusion chapter.