Audience costs are a central feature of many prominent theories of international conflict. We advance the understanding of audience costs by specifying the domestic institutions necessary to generate them. In our conceptualization, audience cost capacity (ACC) is a function of the availability of alternative rulers and the cost of mobilizing against the incumbent. This conceptualization leads to the first measure of ACC that has variation between more and less democratic political systems and variation within autocracies. We subject our measure to a rigorous set of tests that includes addressing selection effects and temporal treatment effects, neither of which have been fully examined in this research area. The empirical analysis offers strong support for the validity of our measure.Which domestic political institutions affect the probability that a domestic audience will sanction its leader for unpopular international actions? Fearon (1994) formalized Waltz's (1959) second image link between the domestic restraints a leader faces and his international behavior, arguing that in some states a leader is an agent of the people: He does their bidding at the international level. Because leaders are subject to a principal, they may face or experience sanctions for unpopular international actions, such as backing down from public threats. Fearon labels these sanctions audience costs. In turn, leaders subject to audience costs are better able to send costly signals to clarify their resolve. Drawing on this logic, Schultz (1999) contends that other states will be less likely to respond to military threats issued by leaders subject to high audience costs than to threats issued by leaders who do not face such costs. Despite the important role audience costs are thought to play in international interactions, it is not clear which leaders, or which sorts of political systems, are likely to be subject to audience costs.A state's audience cost capacity (ACC) is a function of principal-agent interactions. The central debate in the literature is about the domestic political institutions that facilitate or hinder the principal's ability to control the agent through domestic punishment for behavior contrary to the principal's preferences. Existing arguments contend (i) that democratic political systems can generate audience costs but nondemocracies cannot (Schultz 1998(Schultz , 1999; (ii) that certain regime types (democratic regimes, single-party regimes, military regimes, dynastic monarchies, and some well-established autocracies) can generate audience costs (Weeks 2008); (iii) that audience costs are a function of executive constraints (Partell and Palmer 1999); or (iv) that audience costs are a function of ''the stability of domestic political structures'' (Prins 2003:68). We contend that each of these arguments only contains part of the story. The first view does not allow for any nondemocracy to be able to generate audience costs, contrary to Fearon's (1994) original article. The regime type argument does not specify prec...

Why do states participate in United Nations peacekeeping missions? Extant theory revolves around two benefits states derive from participation: the financial benefits participants receive for their contributions and the ability to further liberal norms abroad. Yet, these theories have received limited empirical support. In addition, they cannot explain where and when leaders send troops. To rectify these limitations, I focus on a more straightforward benefit states receive from limiting conflict and providing stability to war-torn regions. Namely, stabilizing conflict areas helps stem the externalities caused from ongoing conflicts, such as refugees. This explanation of participation in peacekeeping predicts who is most likely to send support (those fearing refugee inflows), the size of contribution (increasing relative to the inflows), and where they send assistance (to the specific conflict area producing the externalities). Statistical analysis of all UN peacekeeping missions since 1990 provides support for this argument and reveals that refugee flows better predict who is likely to contribute troops, and to what conflict, than the size of those contributions. While other realpolitik considerations strongly influence which states participate in UN peacekeeping, neither democracy nor state need is a statistically significant explanator of who contributes. However, state need does predict the size of contribution.

Interstate rivalry not only influences a country’s international behavior, but also its domestic conduct. Here, I focus on the connection between interstate rivalry and domestic government mass killing, specifically genocide and politicide. I argue that interstate rivalry has both direct and indirect influences on a government’s decision to use mass violence against its civilian population. Directly, countries engaged in rivalry experience a heightened state of military tension, which increases the likelihood that the country will resort to political mass killing when handling domestic dissent. Indirectly, rivalry increases the likelihood of both inter- and intrastate conflict, which also increases the likelihood of genocide and politicide. Statistical analysis of all country-years from 1955 to 2011 reveals that interstate rivals are more likely to engage in genocide and politicide than are other states. This research illustrates the way in which interstate rivalry influences a state’s domestic politics and shapes the interactions between government and population. It also highlights the importance of how the international threat environment affects a state’s willingness to engage in domestic political mass murder. These findings indicate that rivals do not only engage in the most violent interstate behavior, but also some of the deadliest domestic politics, as well.

Why do some state leaders engage in genocide and politicide while others do not? Extant theory focuses on how large openings in the domestic political structure of a country, such as civil or interstate war, increase the likelihood that a government will respond with violence against its civilian population. This article builds from this previous theory to argue that smaller crises can provide governments with the same incentives and opportunities to engage in political mass murder. Statistical tests of all cases of genocide and politicide since 1955 support this argument. In addition to civil wars, assassinations, coups and strikes increase the likelihood of political mass murder, especially genocide. These findings are important as they caution the international community against fixating on large-scale crises as the impetus for genocide and politicide.

Scholars have not found a consistent connection between state-sponsored mass killing and forced migration. I argue that disaggregating mass killing into its various forms can illuminate these mixed findings. As genocide targets specific groups, the effect of this killing should not have a large effect on creating forced migrants amongst the rest of the population. Conversely, politicides aim to eradicate individuals whom the government sees as a threat. As the focus of politicide cuts across groups, this type of mass killing should affect a larger proportion of the population and lead to greater numbers of displaced persons.