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date: 02 October 2023

Pro-Government Militias and Conflictfree

Pro-Government Militias and Conflictfree

  • Sabine C. CareySabine C. CareyDepartment of Political Science, University of Mannheim
  •  and Neil J. MitchellNeil J. MitchellDepartment of Political Science, University College London


Pro-government militias are a prominent feature of civil wars. Governments in Colombia, Syria, and Sudan recruit irregular forces in their armed struggle against insurgents. The United States collaborated with Awakening groups to counter the insurgency in Iraq, just as colonizers used local armed groups to fight rebellions in their colonies. An emerging cross-disciplinary literature on pro-government non-state armed groups generates a variety of research questions for scholars interested in conflict, political violence, and political stability: Does the presence of such groups indicate a new type of conflict? What are the dynamics that drive governments to align with informal armed groups and that make armed groups choose to side with the government? Given the risks entailed in surrendering a monopoly of violence, is there a turning point in a conflict when governments enlist these groups? How successful are these groups? Why do governments use these non-state armed actors to shape foreign conflicts whether as insurgents or counterinsurgents abroad? Are these non-state armed actors always useful to governments or perhaps even an indicator for state failure?

We examine the demand for and supply of pro-government armed groups and the legacies that shape their role in civil wars. The enduring pattern of collaboration between governments and these armed non-state actors challenges conventional theory and the idea of an evolutionary process of the modern state consolidating the means of violence. Research on these groups and their consequences began with case studies, and these continue to yield valuable insights. More recently, survey work and cross-national quantitative research contribute to our knowledge. This mix of methods is opening new lines of inquiry for research on insurgencies and the delivery of the core public good of effective security.


  • Contentious Politics and Political Violence
  • Governance/Political Change
  • Groups and Identities
  • Political Behavior
  • Political Psychology
  • Qualitative Political Methodology
  • Quantitative Political Methodology
  • World Politics


Pro-government militias (PGMs) are a prominent feature of civil wars. In Iraq the United States sponsored the Sunni Awakening groups to fight against insurgents. Afghanistan formed militias to battle the Taliban. Over the course of the Syrian civil war, the number of militias fighting for Bashar al-Assad has increased and includes Shia militias supported by Iran and Hizbullah from Lebanon. While religious cleavages shape the supply of irregular armed groups in the Middle East, these groups can be found in counterinsurgency (COIN) campaigns across the globe. In eastern Ukraine, pro-Ukraine militias fight against pro-Russia armed separatists, in northern Nigeria the Civilian Joint Task Force battled Boko Haram, and in Colombia rural defense groups assist the government against FARC. While gaining increasing attention in the media, using irregular forces against insurgents has a long history and was a common element of colonial security sectors (e.g., Anderson, 2005; Janowitz, 1977; Thompson, 1966). The British used Assyrian militias in Iraq to assert authority under the auspices of the League of Nations mandate for the territory (Ahram, 2011, p. 62). They used auxiliaries in Ireland, many of whom went on to serve in the Palestine in the 1920s, and they created Home Guards in Malaya and Kenya to defeat insurgencies in the 1950s (Anderson, 2005; Branch, 2009). In fact, many elements of COIN strategies “call for the use of local militias to extend armed presence or allow locals to have a stake in their own security” (Paul, Clarke, & Grill, 2010, p. 62).

Responding to rebel threats with this sort of public–private collaboration occurs across conflict types, rebel actors, and regime types. Assuming a unitary or “Weberian” state actor masks the creativity of governments in combatting insurgents. Across various research fields scholars are increasingly attentive to the activities of armed groups recruited or induced to side with the state (e.g., Blocq, 2014; Jentzsch, Kalyvas, & Schubiger, 2015; Kowalewski, 1992; Lyall, 2010; Stanton, 2015). Attention to these organizations mirrors the wider academic interest in non-state actors and in “not-entirely state” and “not entirely private” (Ostrom, 1990) solutions to policy problems. It is an analytically rich seam of questions and controversies.

We review research on the role of irregular pro-government armed groups in civil wars. After defining pro-government militias, we examine why governments use militias in counterinsurgency campaigns, despite the risks of outsourcing violence. To understand the use of these groups, both the demand and supply side require attention. Using descriptive statistics, we overlay PGM presence on various categories of civil war, building upon the literature on classifying civil wars. We focus the discussion on the effectiveness of militias in COIN campaigns and levels of violence against civilians. We conclude with some challenges for future research.

Pro-Government Militias in the Context of Armed Conflict

Some scholars enlarge the scope of militias to include non-state actors without specific links to government. In a special issue on militias, Jentzsch et al. (2015) use the term militia for an armed non-state actor that is “anti-rebel.” Militias sometimes also include rebel groups (e.g., Bates, 2008; Raleigh, 2016). Instead of focusing on the link to the government, other classifications claim that the link to political actors is analytically more useful than a link to government, as groups may fight for the opposition as well (Schuberth, 2015, p. 306). With changes of government, groups linked to political parties, for example, may no longer be pro-government. But the puzzle remains of why governments, with regular forces available, continue to rely on non-state armed groups. The relationship between the government and militias is diverse and very dynamic, ranging from incorporation to suppression (Staniland, 2015). This review of pro-government militias fits best Staniland’s typological category of “collusion.” We limit our review to armed groups that contribute to counterinsurgency campaigns and that have a link to the government beyond sharing an enemy. We exclude private armed groups of landlords or criminal gangs, unless there is a link to either subnational or national government under civil war conditions.

We define militias as armed groups linked to the government and separate from the regular forces but limit our focus to those operating within the context of counterinsurgency campaigns and civil wars (Carey, Mitchell, & Lowe, 2013, p. 250). The term “paramilitary” may include these groups, but is also often inclusive of regular professional units such as police forces and border guards (Dowdle, 2007). Similar to Jentzsch et al. (2015), we exclude private security firms due to their status as commercial contractors. To further distinguish private security firms from militias, these researchers add territorial conditions, noting that in contrast to military contractors, militias tend to operate at home rather than abroad. We relax the territorial condition and consider militias operating both within and across borders in the context of conflict. But the incentives for governments to contract with these firms (Avant, 2005) may be similar to those that motivate alignment with militias. Our definition also includes surrogate forces, which Hughes and Tripodi (2009) divide into home guards, militias, counter-gangs, and pseudo-gangs. According to their classification, pseudo-gangs are government-sponsored supposedly independent groups that target rebels or terrorists, while counter-gangs (a term for co-ethnic armed groups used in defeating Mau Mau in Kenya) are lightly armed, mobile gangs, often consisting of former rebels, fighting insurgencies. Militias are identified as larger, mobile forces aligned with the government, while they define home guards in terms of the “static defence of villages” (Hughes & Tripodi, 2009, p. 9). Similarly, Clayton and Thomson (2014) and Peic (2014) identify civil defense forces as armed groups that recruit civilians or former rebels, operate locally, and are defensive rather than offensive. This work highlights the significance of ties to the civilian population and whether these militias are local or community organizations (e.g., Daly, 2016; Jentzsch, 2014).

Why do governments create or align with irregular forces when fighting a rebel group? Why do governments not merely strengthen regular forces, which are likely to be better equipped, better trained, and more disciplined? Hughes and Tripodi (2009) point out the disadvantages of militias. They undermine the government’s authority and may not be fully under the government’s control. They are often characterized by internal strife and may lack discipline, accountability, and reliability. Their agendas or ideological preferences may differ from the government (Hughes & Tripodi, 2009). Yet despite these disadvantages, between 1981 and 2007 over 80% of country-years with armed conflict generating at least 25 battle-related deaths included pro-government militias (Carey et al., 2013, p. 255). They are not a phenomenon confined to the post–Cold War era or restricted to certain continents. In the following we review arguments offered to explain the use of pro-government militias in civil wars.

Why Use Militias to Fight Insurgents?

The persistence of irregular forces in counterinsurgency campaigns contradicts expectations of a “developmental” drive to monopolize violence. Without monopoly insecurity develops, which leads to weak and eventually failed states. Bates (2008) simply equates militias with failed states. Klare (2004) argues that paramilitaries accelerate the process of state failure, while Reno (1999) and Hills (2007) suggest that weak political institutions enable militias to form. These arguments see militias less as a deliberate government strategy and more as the outcome of a process over which governments have little influence. Yet the prevalence of pro-government militias in civil war contexts, and the range of regimes using them, suggests they are not only the result of governments being too weak to reign them in. But allowing groups outside the formal security apparatus to carry weapons poses a significant security risk and even the prospect of treason. So why take this risk? The literature suggests several reasons for why governments might purposefully collaborate with or even create these non-state armed forces to assist with COIN operations.

Government’s Demand for Irregular Armed Groups

Governments collaborate with private agencies across a wide range of areas to achieve specific policy goals. Examining policy areas such as education or the provision of parks, Donahue and Zeckhauser (2011, p. 122) argue that governments pursue public–private collaborations for three reasons. Collaboration may provide cheap force multipliers and specialized information, and it may help to maintain legitimacy. Outsourcing also allows for rapid adaptation to changing circumstances. While Donahue and Zeckhauser (2011, p. 20) exclude security tasks from their analysis given the risks entailed in delegating in this area, case evidence on civil war, rebel fragmentation, and on civil defense forces (Bakke, Cunningham, & Seymour, 2012; Clayton & Thomson 2014; Kalyvas, 2008; Peic, 2014; Staniland, 2012) suggests similar benefits from a government’s decision to collaborate with non-state armed actors. We outline four advantages that irregular forces bring for governments during civil war, which are crucial to COIN operations (e.g., Paul, Clarke, & Grill, 2010; Thompson, 1966): cheap force multiplier, local knowledge, legitimacy, and deniability. Outside of civil war contexts they might provide protection from crime or offer a “coup-proofing” counterweight to the regular military (Carey et al., forthcoming).

Carey, Colaresi, and Mitchell (2015) use the reasoning behind public–private collaboration to explain and predict the presence of paramilitary forces. The need for extra forces, local knowledge, and operational flexibility are particularly pressing when faced with an armed insurgency. Regular forces are often overstretched. Using irregular forces boosts capacity swiftly and at low cost. Collaborating with local defense forces, as the Peruvian government did with the Rondas Campesinas to combat the Sendero Luminoso, strengthens the forces fighting the insurgency and provides locals a means of signaling their loyalties (Schubiger, 2013). They receive little training, are usually only lightly armed and cheap to deploy, with the language skills to collect useful information (Peic, 2014, p. 165). Their flexibility and the “incomplete control” (Donahue & Zeckhauser, 2011, p. 32) exercised by government is an additional operational advantage of irregular forces. Militias may make their own decisions on the ground without directions or confirmations from the center.

Knowledge about local grievances, social dynamics, cultures, and histories, as well as information on the location and identity of rebels, are crucial to success in COIN operations (e.g., Kilcullen, 2006, pp. 123–124). Militias offer better local knowledge than regular forces (e.g., Hughes & Tripodi, 2009; Lyall & Wilson, 2009). Locally recruited militias made up of co-ethnics or former rebels (Kalyvas, 2008)—for example, in Kenya or Algeria in the 1950s, or in Iraq in the 2000s—produce intelligence that regular forces are much less able to provide. Clayton and Thomson (2014) argue that civil defense forces have particular value in identifying insurgents. This information is essential for effective operations, yet difficult to obtain for regular forces unfamiliar with the local context. Peic (2014) argues that information is the primary incentive for governments to use of local forces in COIN campaigns. Examining the Awakening groups in Iraq, Biddle, Friedman, and Shapiro (2012) emphasize the knowledge contributions of these groups, and in particular the importance of recruiting former insurgents. Eck (2015) finds further support for the information value of militias, showing that in Myanmar the government was more likely to use militias after military purges had interrupted the intelligence-gathering structures of the military. In asymmetric guerrilla warfare, before the superior resources of the state can be used on the insurgents, they have to find the insurgents. Rebel survival and success depends on avoiding discovery. Irregular forces promise substantial efficiency gains in finding the insurgents.

The central role of this discovery process is illustrated in Nigeria. Failing to manage the threat presented by Boko Haram and subjected to harsh international exposure following the mass kidnapping of schoolgirls, the Nigerian security forces encouraged the formation of vigilante groups. The Civilian Joint Task Force was lightly armed with bows and arrows but supported by the military, who wanted to offload the casualty burden and to access their local knowledge (some of the “civilians” being former rebels)—the state government supplied these irregulars with training, payment, and uniforms (Smith, 2015).

While former rebels organized in militias are not members of the regular forces, neither are they civilians in an ordinary sense. They are likely to have military training and experience, and they also are likely to have a qualitatively distinct level of information, which makes them highly valuable for a government’s counterinsurgency campaign. Kalyvas (2008) provides detailed treatment of pro-government groups formed from “ethnic defection,” where governments value the contribution of those willing to switch loyalty in ethnicity-based insurgencies. States set up “collaborationist structures” that may be populated by civilians—for example, the Turkish government–created “loyal” Kurdish village militias or the German occupier–created militias labeled Security Battalions in Greece in 1944. Kalyvas (2008) notes that these Security Battalions recruited local members as late as 1944, despite Germany’s military reversals. Clayton and Thomson (2014) also include former rebels among their civil defense forces.

Including former rebels in pro-government militias can bolster the legitimacy of the government’s campaign against the insurgents. Militias allow governments to demonstrate local or ethnic support for their cause (Anderson, 2005; Hughes & Tripodi, 2009; Lyall, 2010). The early COIN literature emphasizes the importance of having the support of the local population in order to win counterinsurgency campaigns (e.g., Thompson, 1966). Particularly in foreign power COIN operations, using indigenous forces plays an important role in winning the “hearts and minds” of the population (Enterline, Stull, & Magagnoli, 2013, p. 188). It is easier to undermine the rebels’ cause if the people fighting on behalf of the government are recruited from the population that is supposed to form the basis of the rebel organization.

Finally, governments might turn to irregular armed forces to avoid accountability for violence and establish plausible deniability (Campbell & Brenner, 2002; Carey, Colaresi, & Mitchell, 2015; Mitchell, Carey, & Butler, 2014; Thomson, 1994). International pressure to conform to human rights standards, the threat of international legal action, cuts in economic or military assistance, or simply fear of opprobrium may create an incentive for governments to delegate violence to militias. Using case studies from Africa, Kirschke (2000) and Roessler (2005) link the need for foreign aid to the incentive to outsource the use of violence. Delegating violence to irregular forces provides the government with plausible deniability. Carey et al. (2015) show with a global analysis that governments that might benefit from deniability are most likely to have links to irregular armed groups. Mitchell et al. (2014) find that pro-government militias are linked to more severe forms of repression, suggesting that governments either can’t or won’t control their violence. While COIN strategies are generally characterized by use of violence, governments often use irregular forces for the most egregious forms such as genocide (Ahram, 2014; Alvarez, 2006), not only to avoid accountability but also because members of the military may refuse such orders. In 1982 in Lebanon, Israel used the Lebanese Christian Phalange militia in Beirut. Some regular soldiers in the Israeli Defense Force had warned of the likelihood of civilian casualties if they went into Beirut (see Mitchell, 2004; Schiff & Ya’ari, 1984, pp. 215–216). Biberman (2016) claims that governments might forgo deniability and instead publicly collaborate with irregular armed forces if the war effort is generally supported by the population.

While the lack of complete control over irregular forces is an important asset for a government trying to root out an insurgency, delegation also offers an advantage when trying to influence the power balance abroad. Supporting rebel proxies reduces the cost incurred by engaging in conflict directly (Salehyan, 2010). Avant (2005) identifies similar incentives in her analysis of private military contractors. Contracted from abroad, they may encourage more “adventurous” foreign policies, and for democracies they may permit operations that might otherwise lack public support (Avant, 2005, p. 259). She argues that strong states should be in a better position to control contractors to avoid the negative externalities of outsourcing the use of violence. Applying a two-level game, Bapat (2012) suggests that leaders systematically take advantage of the limited control they have over irregular forces when trying to influence an armed conflict abroad. Sponsoring militias in a foreign conflict amounts to costly signaling and “increases the probability of both bargaining failure and of a negotiated settlement favorable to the sponsor” (Bapat, 2012, p. 1). These calculations might also be behind Russia’s involvement in Ukraine in 2015. Although it is generally recognized that Russia actively supports pro-Russian rebels in Eastern Ukraine, Putin insists that these groups act independently of the Russian government, and it is not clear that Russia can be held accountable.1 The same strategy was used with respect to the “Little Green Men” that occupied the Crimea in 2014. Using irregular forces has allowed Russia to influence politics in neighboring regions while denying any responsibility and potentially strengthening its bargaining position, since any deal will have to be acceptable to the pro-Russian militias. Not without regular forces, Russia aligned with militias in Afghanistan, in Chechnya, in Georgia, and in Ukraine. It is not the only country working with irregular forces to shape the power balance in other countries. The United States and the United Kingdom relied on militias in Iraq and Afghanistan (Ledwidge, 2011). Prior to 2003, Saddam Hussein used militias both for counterinsurgency and during the conflict with Iran.

The Supply Side

Despite the range of benefits PGMs provide to governments, the logic of collective action (Olson, 1965) tells us that the supply of groups cannot be taken for granted. Such organizations may form independently, or they may be formed by the state. Individual differences in beliefs, interests, and circumstances and, where violence is involved, a propensity to let others take the risks of exposing themselves to danger makes spontaneous solutions to the “massive coordination dilemma” unlikely. Some suggest solutions will only develop with elite participation (Weingast, 1997, p. 246). But there are examples of decentralized solutions where groups form to address some common security threat, perhaps instigated by local elites and on the basis of some established social, economic, religious, or political cleavage, and which then may have some incentive to collaborate with the government (e.g., Wood, 2008).

In Mozambique, Jentzsch (2014) argues that the strategic context and stalemate between rebels and government forces led to the formation of community-initiated militias. In Peru in the 1970s, peasant communities formed self-defense groups initially to protect themselves against cattle thieves. In the 1990s these rondas campesinas were organized against the Maoist insurgency and received support from the government, mostly in the form of weapons. In 1991 President Fujimori gave these groups a legal status as self-defense committees (Fumerton, 2001; Schubiger, 2013). In South Sudan, at the instigation of tribal leaders, and after civilian authorities and the police reportedly refused help, tribal militias formed to protect themselves from, and wreak vengeance upon, neighboring tribes (Blocq, 2014). They formed independently, but then collaborated informally with army commanders and received material support, including tanks (Blocq, 2014, p. 717).

Some groups turn to governments to supplement their resources. In Iraq, the pro-government Awakening militias were born out of a struggle between rival militias. Alliance with the government and U.S. forces gave access to arms. Former rebels in Sri Lanka or Kashmir reorganized on the government side and contributed to the counterinsurgency campaigns. Staniland (2014, p. 174) argues that the Karuna Group that split from the Tamil Tigers was a development that the government made the most of rather than created.

If no groups exist to ally with, governments provide the necessary material and ideological incentives, or the coercive pressure, to create these groups. While the government has coercive and material resources to solve the coordination dilemma, there may be a political benefit in presenting the militia as a spontaneous grassroots initiative. It serves as an indication of popular support for the regime rather than the insurgents. India provides an example of this dynamic and the importance of the narrative behind delegation and alliances with irregular groups.

Responding to the Maoist insurgency in India in 2005, the government encouraged the formation of a village militia, the Salwa Judum. The Salwa Judum was “touted by the government as a spontaneous people’s movement” (Sundar, 2006, p. 3187). The government fostered the belief that it was a popular response to the Maoist threat, but used a mix of coercion and inducement to create the militia. After all, recruits “feel immensely vulnerable to retaliatory action by the Maoists” (Sundar, 2006, p. 3187). Members of Salwa Judum were given the status of Special Police Officer. Some members “signed up for the money on offer, and the shiny new bicycles and motorbikes still wrapped in plastic at the Dornapal police station” (Economist, August 16, 2006). With this organization, villagers were being “pitted against each other on a scale unparalleled in the history of Indian counter-insurgency” (Economist, 2006). But the Indian government has repeatedly “pitted” villagers against each other when faced with insurgent threats. In 1950 in Hyderabad, the government created Home Guards or Village Defense Squads. These organizations were led by local Congress Party politicians or landlords, “forcibly recruited by the police,” and allowed to operate with impunity and incentivized to kill insurgents (Kennedy & Purushotham, 2012, p. 843). Impunity also characterized the operation of the Salwa Judum. Impunity is an incentive for violent collective and individual action that only the government can offer. For the militia and its members, the grant of sovereign authority lowers the expected costs of its private violence. Researchers investigating the life cycles of these groups face the challenge of evaluating the government’s description of these groups as spontaneous or grassroots. Weingast’s (1997) intuition that elites, local or central, solve the coordination dilemma requires investigation.

Moving from the government and group incentives to the individual level, we know little about what motivates anyone to join a PGM. Material incentives reportedly played a role with the Salwa Judum, and Hughes and Tripodi (2009) argue that individuals join if they expect to receive financial incentives or bribes, to carry out (preemptive) revenge, or because they have been threatened. Using survey data from the Colombian civil war, Arjona and Kalyvas (2011) compare individual and group-level reasons for joining a rebel or paramilitary group. They find that compared to former FARC members, former members of the paramilitary forces seem to be more materially motivated. They also show that whoever controls a locality is likely to recruit members to its organization. Gutiérrez-Sanín (2008) contrasts the mobilization and recruitment of rebels and militia organizations in Colombia. Research on Algerians who sided with the French and Greeks who collaborated with the Germans suggests the motivations for ethnic defection include revenge, pressure, and coercion, in addition to material resources (Evans, 2011; Kalyvas, 2008). In Chechnya, some pro-government groups recruited individuals involved in blood feuds and who had nowhere else to turn and could not return to their own communities (Šmíd & Mareš, 2015).

Types of Civil Wars and PGMs

If general incentives drive demand for these groups, and if the government subsidizes the creation of them, then militias will not be restricted to states at a particular point on the path to development or to a particular region of the world. We note that some theoretical arguments point to the importance of specific historical trajectories (Ahram, 2011), but if we accept that militias can appear anywhere, we need to explain why PGMs might be more likely to be used in some types of conflicts compared to others, since they are not present in all conflicts and not at all times.

The UCDP/PRIO Armed Conflict Dataset (Gleditsch, Strand, Eriksson, Sollenberg, & Wallensteen, 2002; Themnér & Wallensteen, 2014) distinguishes between two types of civil wars depending on the driving factor behind the conflict. Governmental conflicts are about the government, e.g., the political system or the replacement of the central government; territorial conflicts are about the insurgents’ demands for territory. Figure 1 shows the percentages of governmental conflicts per year that had at least one PGM, using information from the Pro-Government Militias Database (PGMD) (Mitchell & Carey, 2013). The graph differentiates between informal PGMs, which have only a loose link to the government, and semi-official PGMs, which are officially recognized and often formally included within the structure of the security forces, while being separate from regular military or police (Carey et al., 2013).

Figure 1. Pro-government militias in governmental conflicts.

While the proportion of governmental conflicts with informal PGMs increased from a low of 20% in 1983 to 75% in 2003, the proportion of such conflicts with the semi-official PGMs declined. In 2006 half of all governmental conflicts had both informal and semi-official PGMs. The increase in the proportion of conflicts with informal PGMs might reflect an artifact of the data and increasing media coverage of such forces over time. Alternatively, it might reflect the increasing benefit of denying responsibility for violence since the end of the Cold War, which makes outsourcing to informal PGMs particularly attractive. With the rise of human rights on the international agenda, for example, the EU’s Copenhagen Criteria of 1993 and political conditionality for foreign aid, governments have an increasing incentive to distance themselves from repression.

Figure 2 plots the proportion of territorial conflicts with PGMs between 1981 and 2007. Again, the percentage of conflicts with informal PGMs sharply increases in the mid-1990s. But throughout the period more conflicts feature semi-official PGMs compared to informal militias, suggesting that governments are less willing to rely on irregular forces that pose the most severe delegation and control problems. Additionally, semi-official PGMs allow the government to publicly demonstrate a local or ethnic component to counterinsurgency that can be useful in tackling the secessionist struggle.

Figure 2. Pro-government militias in territorial conflicts.

For an alternative classification, Kalyvas (2005) uses the type of warfare between government and rebels. Conventional civil wars are conflicts with resource parity between the two actors at a high level of resources. Symmetrical non-conventional (SNC) civil wars also have parity between the actors but at a low level of resources. Finally, irregular civil wars have high incumbent resources but low rebel resources. Figures 3 and 4 combine data on these different types of civil wars based on Balcells and Kalyvas (2014) with the PGMD.

Figure 3. Different types of warfare and prevalence of PGMs

For each type of civil war—conventional, irregular, and symmetrical non-conventional —Figure 3 plots the percentage of the respective conflict type with PGMs. The unit of analysis is the conflict. The dark blue columns are the percentage of civil wars that had at least one PGM in the first year of that type of conflict, while the light blue columns represent the percentages with at least one PGM in the final year of the conflict. The data range from 1981 to 2007. Conflicts ongoing in 2007 were excluded. The figure differentiates between informal and semi-official PGMs, although the patterns are very similar. A larger percentage of conventional civil wars have PGMs at the beginning rather than the end of the conflict. This trend is slightly more pronounced for informal PGMs, and raises the question of how PGMS merge, die, or “fade away,” which has received little attention in the research literature (but see Staniland, 2015, for a discussion of the strategic choices of incorporation and suppression). Informal PGMs are most likely found when an irregular civil war comes to an end. Governments that did not have links to irregular forces at the onset of the irregular conflict did so when the conflict ended. This appears consistent with the finding that militias are usually not present at the beginning of the conflict but on average appear four years into the conflict (Peic, 2014, p. 175).

In irregular and particular SNC conflicts, the proportion of conflicts with informal PGMs is higher at the end than at the start of the conflict. The sharp increase in informal PGMs across SNC civil wars when these types of conflict end could reflect the multiplication of irregular forces in weak states. During conflicts in weak states, armed groups might “bandwagon” to benefit from being aligned with the government, for example, with weapons, payment, or immunity. If the conflict is ethnic, then Kalyvas suggests that ethnic defection increases as conflicts reach the “latter stages” (2008, p. 1051).

Figure 4. Different types of warfare and number of PGMs

Figure 4 plots the number of PGMs found in the different types of civil war, at conflict start and conflict end. While the share of irregular conflicts with PGMs increases over the conflict cycle, the actual number of PGMs drops. What explains these patterns? Do governments actively merge or reduce the number of PGMs when fighting a guerrilla war, or do governments only get involved in or dragged into irregular warfare if they have distributed their authority to use violence across a large number of irregular forces? Future research has important questions to tackle on the life cycle of PGMs and the dynamics of civil war.

How Effective Are Militias, and What Price Do Civilians Pay?

While many conflicts feature pro-government militias, do they provide an advantage to governments and prevent an outright loss to the rebels, or can they turn a conflict into a government victory? What price do civilians have to pay when PGMs are involved? The literature provides a mixed picture of PGM violence against civilians. Analyzing the conflict in Chechnya, Lyall (2010) shows the tactical effectiveness of using co-ethnic, locally informed militias in comparison to regular Russian troops. He uses Geographic Information System mapping (GIS) and news sources to collect data on the location and number of militia and on regular force operations and insurgent attacks in the Chechen conflict and a matching technique for the regression analyses. His findings suggest that these groups contributed to regime security. It is less clear how to assess the comparative harm done to the local population by the different types of forces. While Lyall finds Russian forces killed and disappeared more individuals, the militias kidnapped greater numbers (2010, p. 14). He quotes a local non-governmental organization (NGO) representative: “The kadyrovtsy are much more dangerous for local residents in terms of persecuting entire families or kidnapping individual relatives … The federal [Russian] troops simply don’t have such complete information about the local residents” (Lyall, 2010, p. 15). Šmíd and Mareš’s (2015, p. 15) qualitative case study of the Chechen conflict also finds that Putin’s policy of “Chechenizing” the conflict was successful. Russia enlisted Chechen clans as paramilitary forces, but according to their account at the price of violent excesses.

Using micro-level data from the Philippines between 2001 and 2004, Felter (2007) compares the military effectiveness of elite forces, regular forces, and civil defense forces. He evaluates effectiveness along four dimensions: striking targets effectively with minimum collateral damage, central monitoring with decentralized execution, access to local information, and signaling credibility in victory. He shows that the civilian defense forces, the Civilian Armed Forces Geographical Units, perform worse than the other types of forces across all categories. Local knowledge appears to lead to feuds and vendettas and makes them targets for rebel violence. As a result, they suffer much higher casualties than regular or elite forces, even controlling for their smaller size and possible differences in deployment strategies.

Additionally, Felter (2007) shows that the proportion of firearms that were lost is much higher among the indigenous forces compared to regular and elite forces. This finding highlights the risks of yielding a monopoly of violence. Felter explains these failures with poor leadership and supervision. When elite forces lead the indigenous forces, they become far more effective than either the elite forces or the regular forces (Felter, 2007, p. 26). Similarly, in Algeria, using local forces to find the guerrillas and French paratroopers to kill them was effective: “within months the ALN had lost half of its soldiers killed, captured, or converted to the French cause” (Evans, 2011, p. 245). These findings suggest that the qualities that irregular forces bring to COIN can be more fully exploited when problems of delegation are reduced by leading them with highly trained and specialized forces. But the wider evidence on civilian violence is mixed.

The collaboration between the Awakening militias in Iraq and U.S. forces provides another example where highly professional forces benefit from the knowledge and the skills of local irregular forces. In their analysis of the success of the Iraq Surge, Biddle et al. (2012) argue that neither the irregular forces nor the American troop surge on its own was sufficient to reduce the violence in Iraq in 2007. They identify the intelligence on the insurgency collected from the Awakening groups, the fact that they were no longer fighting against the coalition, and the consequences this alliance had for Shiite militias as their principal contributions to the success of the surge, noting again rising levels of violence against civilians (Clayton & Thomson, 2014). Biddle et al. (2012) contrast the forces in Iraq with those in Afghanistan. They argue that the militia forces the coalition created in that theater, the Afghan local police, was unable to recruit former rebels—which prevented a similarly successful outcome. Algeria under the French, Kenya under the British, or more recently in Kashmir, Sri Lanka, and Chechnya all saw former rebels organized to fight alongside regular forces to reverse rebel gains.

With some nuance depending on the type of militia involved, a body of research suggests that these militia forces put civilians at risk. In defeating the Mau Mau insurgency in Kenya, these local forces inflicted significant harm on civilians: “The Home Guard thus represented state-sanctioned and sponsored terror intended to bring the population of Central Kenya under the control of the incumbent regime” (Branch, 2009, p. 87). The British government also recruited “counter-gangs” or “pseudo-gangs” of former insurgents to operate alongside the Home Guard and regular forces. “Security Forces had better weapons … but they had firmly fastened one of their hands behind their back with a cord of legal difficulties which was not the case with the irregular forces” (Kitson, 1960, pp. 44–46). In Mexico in the 1990s, ruling party–based militias are reported to have been responsible for 15,000 murders in the wake of the Zapatista rebellion (Mazzei, 2009, p. 25). With cross-national conflict data, Cohen and Nordås (2015) suggest that militias that recruit children are linked to higher levels of sexual violence. Stanton (2015) argues that if militias and insurgents come from the same constituency, then militias are less likely to attack civilians. Comparing different types of militias in East Timor, Barter (2013) concludes that militias that were created by the government were more likely to attack civilians, while those that developed in self-defense against powerful rebels were more likely to behave defensively.

Using irregular forces thus carries significant risks. Kowalewski (1992) contrasts the “benevolent” with the “critical” perspective of using irregular forces. While the benevolent perspective emphasizes “the exercise of popular sovereignty” (Kowalewski, 1992, p. 72) by using private citizens to fight rebel groups, the critical view highlights limited accountability of such irregular forces, as well as their pliability by a (foreign) elite minority and their questionable, and sometimes forced, recruitment of fanatics (Kowalewski, 1992, p. 72). He analyzes five daily newspapers from the two largest cities in the Philippines during the late 1980s to evaluate whether paramilitary groups in the Philippines corresponded more closely to the benevolent or the critical perspective. Across a large range of specific indicators, Kowalewski finds support for the critical view of paramilitaries (1992, pp. 79–80). Other work suggests that pro-government militias increase the likelihood of “agent-centered violations” such as extrajudicial killings, torture, and disappearances, which are violations that fall within the capacity of individual agents and from which there might be a plausible private benefit, be it revenge, extortion, or some gratification from the violence itself (Mitchell et al., 2014). Irregular armed groups are likely to be less well equipped to train recruits and inculcate codes of conduct. Furthermore, governments might be tempted to use these groups to shift blame and alleviate legal difficulties for controversial violence (Carey et al., 2015). In contrast, some recent research challenges the usefulness of a principal-agent approach for understanding the violence committed by militias, arguing that social cohesion and diffusion (Cohen & Nordås, 2015) and strategic decisions (Stanton, 2015) provide better explanations. As empirical measures improve, we expect to have a clearer picture of levels of “agent-centered” violence attributable to different types of armed group organizations and how well these fit with the implications of a principal-agent approach.

Some studies suggest that civil defense forces contribute to effectiveness. Analyzing irregular civil wars between 1944 and 2006, Peic (2014, p. 171) finds that governments that used civil defense forces (CDFs) were defeated more rarely than those that did not use CDFs. The multivariate analyses suggest that using CDFs substantially improves governments’ chances of defeating an insurgency. Analyzing 30 counterinsurgencies, Paul et al. (2010, p. 63) show that 25 used militias or “community policing.” While 19 resulted in COIN losses, the authors caution that the use of militias cannot alone account for the losses. In 15 of these 25 COIN operations, militias were at cross-purposes, and 13 of those 15 ended in COIN losses (Paul et al., 2010, p. 63). These insights point at the core problems associated with delegation. Multiple agents complicate monitoring and likely increases discretion. Discretion can be an advantage to the principal in allowing agents to respond effectively to local conditions—what Donahue and Zeckhauser term “production discretion” (2011, p. 50)—but it becomes a disadvantage when discretion permits opportunism and shirking. We expect militias are more likely than regular forces to pursue private interests within the governments’ COIN operations. This might result in the use of excessive violence, which some studies suggest is counterproductive in fighting insurgents (e.g., Daxecker, forthcoming; Lafree, Dugan, & Korte, 2009). Paul et al. caution governments to ensure that militias do not resort to “disproportionate or illegitimate uses of force” (2010, p. xxiv). The divergent literature on the impact of government militias on human rights and civilian welfare, on COIN success, or state failure suggests that investigating the consequences of these groups is an important component of the research agenda.

PGMs in the Aftermath of Conflict

Figure 3 shows that pro-government militias are present in over 60% of irregular civil wars at the point when these conflicts end. So what happens to these groups? How do they affect post-conflict stability and security? Mueller (2003) argues that particularly in weak states, armed groups often engage in criminal activities during civil wars—even more so when irregular armed groups such as mercenary forces or death squads are used. Focusing on the disarmament and demobilization of militias in Afghanistan, Giustozzi (2008) points out how difficult it is to effectively disarm and delegitimize militias. PGMs may become the private armed forces of warlords (Marten, 2006). Wehrey (2012) describes in Foreign Affairs the conundrum posed by militias in Libya. After the elections in June 2012, militias were used as hired guns while disarmament processes were underway. The failure to disarm these forces seriously affected the stability not just of that country, but of the whole region. Mueller suggests “the key to controlling the remnants of war is the establishment of competent domestic military and policing forces” (2003, p. 511). This might be particularly difficult at the end of a civil war fought by a diversified security sector.

Civil war may provide these groups with opportunities for private gain (Hughes & Tripodi, 2009), while peace limits opportunity. Furthermore, we know that some militias have an ethnic membership and the ethnic basis of conflict is a theoretically important dimension for the duration of a conflict (Wucherpfennig et al., 2012). Ethnically defined militias may polarize ethnic groups, which creates long-term mistrust that further complicates post-conflict reconciliation. As we know from the literature on rebel groups, having multiple actors likely makes it harder to achieve a peace agreement and end the fighting (Bakke et al., 2012). If they benefit from ongoing conflict, militias might act as spoilers to peace agreements. In short, there are reasons to expect that the presence of pro-government militias will make a conflict last longer, produce increased levels of violence and abuse, and make the post-conflict period more volatile. Putting civilian defense under the leadership of regular forces might provide a way of harnessing the advantages of irregular armed forces while reducing the risk associated with them. But even in circumstances where militias act in concert with highly professional regular forces, they may bring substantial harm to the civilian population, as with the Israeli army’s use of the Lebanese Phalange militia in Lebanon in 1982, or the use of these forces by the Americans in Iraq or the British in Kenya.

Open Questions

Research focusing on the actors involved in conflict, instead of simply the structural conditions, and abandoning the assumption of unified forces on either side provides us with a richer understanding of the dynamics of civil war. Initial insights into the role of irregular forces aligned with the government, piecing together evidence from a disparate case literature and some quantitative cross-national studies, opens up new questions for future research. As in other research fields, an important first step is to sort out meaningful dimensions for classifying these organizations. While militias are found in conflicts around the world, they vary in their ties to governments or particular leaders, in their visible or clandestine activities, in their recruitment and connections to other societal, political, or economic organizations, in their size, and in national or local presence. What explains these different characteristics of PGMs, and how do these characteristics influence the effectiveness and long-term consequences of these groups on stability and peace? Also, in what types of conflicts are militias likely to develop over the course of fighting, and when are PGMs likely to escalate a conflictual situation to civil war? While case studies have provided us with important insights into these topics, more research using different approaches and covering different areas across time and space is needed for a deeper understanding of the roles of PGMs in conflict.

Accepting that there is some debate about the usefulness of a principal-agent approach (see Cohen & Nordås, 2015; Stanton, 2015), we need to know more about the details of the “contract” between these groups and their respective governments. For political scientists the structure of the relationship between the state and its armed non-state actors, the presence or absence of monitoring mechanisms and sanctions, suggests the likelihood of “adventurous” policy and the willingness of a government to evade accountability. We need to know the lines of communication between groups and government. Is there a functional equivalent of the chain of command found in regular forces? When are militia members most likely to shirk? These questions are important to research on global accountability, the state’s responsibility to protect, and to compliance and accountability issues for the international community (Grant & Keohane, 2005). Thomson (1994) describes the 1856 Paris Declaration by which the major powers agreed to end their use of letters of marque authorizing pirates to fight and loot on behalf of the state. There appears to be little progress in that direction for state authorization of irregular forces that fight on land. A ruling by the International Criminal Tribunal for the former Yugoslavia (ICTY) involving Arkan’s Tigers suggests that state officials, even if they train and arm these groups, may be freed of responsibility for their criminal conduct.

A better understanding of when these groups enter and exit a conflict is highly relevant for policymakers. Given the risks entailed, the expectation is that these groups are a desperate measure (Downes, 2006) or last resort (Peic, 2014). When do governments turn to these groups? What role does loyalty, ideology, revenge, material gain, desperation, and coercion play in their recruitment and type of membership (Staniland, 2014; Weinstein, 2007)? Furthermore, the contract is likely to entail some post-conflict expectations on all sides. As parties are added to a conflict, the conflict may become more difficult to settle. The impact of these groups on conflict duration, and more specifically on the outcome of negotiations where these groups have been involved, requires investigation. Do additional actors on the government side have the same impact on the conflict as increasing actors on the rebel side? If larger numbers on the side of the rebels results from “fragmentation” (Bakke et al., 2012) and the internal division of rebel forces, “force multiplication” or adding new forces is more likely to reflect the process of increasing the number of actors on the government side. And what does the exit of these groups entail? Are they re-integrated? Does their violence shift to criminality? What is their legacy? An innovative subnational study of post-conflict violence in Guatemala suggests these groups live on long after their wartime organization (Bateson, 2013). Survey and interview evidence from Colombia suggests that the local or community-based nature of these groups contributes to their longevity (Daly, 2016). Ties to a community, which from a principal-agent perspective may make monitoring and control easier, can help us understand their behavior during and after conflicts.

Irregular forces fighting on the side of governments may evoke images of a bygone era, of Lawrence of Arabia. Our theories of the state suggest they are a thing of the past and that security is a sovereign task. But sovereign tasks are less preciously held than anticipated. On ill-defined battlegrounds around the world, these groups continue to offer services to governments. They cheapen the material and political costs of conflict. While the short-term advantages to a particular government may be apparent, researchers need to gather the data and develop our theoretical and empirical understanding of how public–private collaboration in the security area contributes to core public goods.


We are very grateful to Anna-Lena Hönig and Anita Gohdes for their excellent research assistance and Adam Scharpf for his invaluable comments. Sabine Carey has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant Agreement n° 336019. Neil Mitchell and Sabine Carey received funding from the Economic and Social Research Council (ESRC), UK, RES-062-23-0363.


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  • 1. For a brief discussion of the difficulties holding Russia accountable for Ukraine rebels, see the BBC News website.