Political stability can be defined as the reproduction of the status quo in political life. The term and its mirror image—political instability—have a decidedly behavioral connotation in most contemporary social science research. As seen by many scholars, political stability is the outcome of interactions by relevant political actors that reproduce the status quo in political life. Conversely, political instability results from interactions that challenge the status quo. To be empirically useful, however, the character of political behavior and whose values or expectations it fulfills (or violates) have to be specified.
The earliest theories of political stability concerned themselves with its societal prerequisites. The prominent sociologist Talcott Parsons (1902-1979) equated political stability with collective legitimacy and the systemic support it afforded. According to Parsons, legitimacy is "the higher normative defense against the breakdown of a system of social order" (Parsons 1963, p. 57). Parsons argued that if citizens did not view the political system as legitimate, they would be particularly prone to support political protest and other forms of antigovernment action. David Easton (b. 1917) further broadened the meaning of legitimacy to include citizen’s perceptions of government institutions as fair, responsive, and valuable.
The difference between citizens who viewed the government as illegitimate but did not join in collective action and those who took part in political protest did not figure prominently in Parsons’s work. For Parsons, the potential for disorder increased with the loss of public confidence in the government. Likewise, Easton argued, only diffuse support through the population gives the system political stability. In their concern with mass political attitudes, these social scientists went beyond a narrow focus on mass political behavior. Their theories, however, were judged as status quo-oriented and suffused with expectations of political behavior and functional roles characteristic of advanced industrialized democracies.
Beginning in the 1970s, social scientists turned their attention to political institutions and the patterns of political behavior they generate. Work on political stability has linked the durability and survival of political regimes with patterns of political behavior. The literature emphasizes institutional consistency and how it affects the behavior of political elites, but mass political attitudes can be used to explain the choices elites make given particular institutional configurations.
Scholars of political institutions have classified polities based on three attributes: (1) procedures for selecting the chief executive; (2) constraints on executive decisionmaking authority; and (3) extent of political participation. This classification results in three basic types of political systems: autocracies, anocracies, and democracies. Autocracies are politics where authority is concentrated and unchecked, whereas democracies are politics where power is diffused. According to scholars of political conflict, anocracies are institutional hybrids combining characteristics of both democracy and autocracy.
Fully autocratic and democratic regimes exhibit the greatest stability. This stability results from the compatibility of their institutions with the behavior of politically relevant actors. Institutionally inconsistent regimes (those exhibiting characteristics of both democracy and autocracy) lack these self-enforcing characteristics. Accordingly, the least stable political systems are autocracies with highly regularized procedures for selecting the chief executive but with high levels of political participation. The most unstable configuration for polities with an elected executive is one where the executive is highly constrained, but the electorate is very small.
The conclusions of institutional scholars can be summarized by a curve with an inverted-U shape: low and high levels of institutional development result in political stability; intermediate levels stimulate political instability. Institutions affect the cost-benefit analysis associated with challenges to authority. The interaction of political actors, in other words, is conducive or detrimental to the distribution of authority in a system of governance.
The work of institutional scholars highlights elite interests and behavior. Mass political behavior, as Parsons and Easton demonstrated, is also necessary to understand patterns of political stability. As the expectation that elites will respect the outcomes of democracy increases, the rewards for compliance with the rules of democracy also increase. This is another way of saying that what is important for a political system is whether institutional continuity is in the interest of the relevant political elites. By raising the cost of noncompliance with the democratic rules of the game, the public has a role to play in the cost-benefit analysis of elites.
One question that was not addressed in studies of political stability until the early twenty-first century is the compatibility of leadership survival with regime stability. Scholars have noted the apparent paradox that while democratic polities are durable forms of government, democratic leaders exhibit a high turnover rate. At the same time, autocratic leaders remain in office for remarkably long periods. The puzzle then is why autocrats tend to remain in power longer than democratic leaders even though autocracies as a group are not more stable than democracies.
According to the selectorate theory of political survival, elites and their supporters in stable democracies have more to lose in the long run by clinging on to power and suppressing their political opponents than by waiting for their turn to be (re) elected to office. Consequently, they choose democracy instrumentally and in the process help increase its legitimacy as a form of government. Autocrats, on the other hand, depend on a narrow coalition to win and remain in power and are widely perceived as illegitimate. As a result, democracies constitute a remarkably stable form of regime even though their leaders last half as long as autocrats.
The selectorate theory explains why protest is prevalent in democracies and rebellion predominates in authoritarian regimes. Because democracies are seen as more legitimate forms of government than autocracies, political protest does not level off as a country democratizes. Yet democracies do not have a demonstrable need to repress peaceful or routine protest. By reducing levels of socioeconomic and political inequality, democracies dampen the temptation to engage in rebellion, which is prevalent in authoritarian settings. Finally, democratization creates political opportunities to engage in more conventional forms of collective action, a point the selectorate theory is well equipped to explain.