Management of Civil Wars and Genocidal Violence: Lessons from Statistical Research

Birger Heldt
Senior Researcher
Folke Bernadotte Academy
Ministry of Foreign Affairs, Sweden

 The genocides (G/P) and mass atrocities particularly in Rwanda, Bosnia, Sierra Leone, the Democratic Republic of Congo (DRC) and Darfur have generated a debate on whether and how peacekeeping operations (PKOs) should, and could, halt such events (Welsh 2006; Seybolt 2008. See also Donald 2002; Findlay 2002; Stephens 2005; Yamashita 2008). At issue is whether PKOs should use force beyond self-defence against perpetrators of atrocities, or even intervene for the sole purpose of halting such events. In conjunction with this there has been a movement in the direction of a larger permissiveness for UN PKOs (ranging from self-defence, to reactive and proactive use of force, and logistical support to - or joint operations with - one of warring parties) as express in UN PKO mandates, the UN's new capstone doctrine for peace operations (United Nations 2008) as well as actual praxis in the field (Donald 2002; Stephens 2005; Yamashita 2008).

The policy and scholarly debates have addressed this issue with the help of anecdotes and compelling and insightful arguments. Missing from the debate are insights from a systematic approach that builds on historical data across many PKOs and atrocities. In particular, knowing more about the historical track record of PKOs, and more about the causes of atrocities, can assist in offering broad policy guidelines that rest on solid empirical ground. Such guidelines may serve to complement - but not replace - fine-tuned case insights that are able to take into account important case specific details.

This paper assesses this question foremost on atrocities against civilians in the context of civil wars. "Atrocities" refers to deaths due to the intentional killing of civilians (non-combatants), and as such excludes indirect deaths caused by disease, starvation, and crossfire. This category of violence includes some elements, such as targeted violence by governments, of standard definitions of genocide and politicide (G/P), but excludes others, namely intentional starvation and other indirect methods. Moreover, and unlike common definitions of genocide, it does not require that victims of violence can be distinguished on ethnic or political grounds, or that governments carry out violence.

In order to clarify the magnitude of atrocities the next section offers an overview of historical pattern and character of the interrelated phenomena of civil wars, battle-related deaths, genocides and atrocities. To put the figures in a broader perspective, the section highlights the absolute as well as comparative magnitude of atrocities over time, and takes a closer look at the DRC. The following section discusses the causes of atrocities as identified by statistical research, whereas the next assesses the historical track record of UN PKOs and non-UN PKOs in halting atrocities. The last section is an attempt to summarize the findings with the normal caveat, and to suggest an agenda for research that may serve to generate more solid and relevant findings.

The Magnitude of Atrocities

Not only has the annual number of armed conflicts and G/Ps decreased drastically since the end of the Cold War, but so has also the annual number of direct war casualties.[1] Figure I below covers 1948-2007 and shows a peak in the number of ongoing conflicts and G/Ps in 1991, after which there has been a decrease of about 40% in conflicts and around 90% in G/Ps.[2] While there were fewer conflicts before the 1970s than today, the number of states and thus also the potential number of states with exposed to civil and interstate wars, have doubled after the second World War. One insight from figure I is that the historical conflict pattern shows "stickiness" or inertia: short-term increases/ decreases in absolute (not relative) numbers are limited. Annual changes by some ten conflicts have historically taken at least four years to materialize. If history is a guide to the future, then the number of armed conflicts will continue to not show any major changes in the short-term.

As for the medium- to long-term development, a simulation covering 2010-2050 and based on the most recent statistical models of civil wars, offer similar predictions: at worst, the global number of conflicts will stay virtually unchanged, and at best there will be a small global decline (Hegre at al., 2009). Regional variations are predicted, and involves more conflicts in eastern, central and southern Africa, and less or unchanged numbers in other regions. Everything else equal, this means that we should continue to see more instances of genocides and mass killings in Africa as compared to other regions. This suggests that the global demand for peacekeeping will remain unchanged for the foreseeable future. Moreover, and assuming that needs is an important conditioning factor behind the UN's decisions to deploy PKOs, we are led to expect a continued as well as increased focus on Africa, and also continued challenges of the same types experienced in past and present African cases.


Armed Conflicts and G/P, 1948 - 2007


While showing an overall positive development from the early 1990s and onwards, the figure does not reveal the extent of crossfire casualties and atrocities against civilians, which is the important question. Figure II below covers the same time period and shows on the one hand the number of direct war deaths in terms of military and civilian battle-related deaths, and on the other hand the number of civilians wilfully killed by warring parties.[3] Note that the figure does not include the mortality of these conflicts, in terms of the difficult and often controversial estimates of the number of civilians dying because of disease, starvation, brought along either accidentally by the war, or by the warring parties as part of a war strategy or G/P, and which are often many times larger than the battle-related deaths.[4] In just the case of the DRC, excess deaths have been very conservatively estimated to be at least around 1000.000 during the course of the most recent conflict (Human Security Report 2010).

Battle Related Deaths and Atrocities 1948-2008

The annual direct war deaths peaked at around 600.000 during the Korean War in the early 1950s, the Vietnam War and the war in Cambodia during the late 1960s and early 1970s (400.000), and the 1980s (300.000) when the data is dominated by the wars in Ethiopia, Afghanistan and the Iran-Iraq war. During the 1980s the annual number of battle-related deaths was close to 300.000, while from 1992 and onwards it is on average well below 100.000. Since the annual number of battle-related deaths has decreased proportionally (about 2/3) more than the number of armed conflicts (about 2/5) during 1989-2007, this means that conflicts have on average become around 50% less deadly in terms of annual and direct battle-related deaths. For the period 1950-2007, the average annual battle-related deaths per ongoing conflict has actually decreased by 90%, although this is mainly due to the statistical impact of a handful of large wars mentioned above (cf. Human Security Report 2009).

Concerning deaths caused by atrocities, the peak in 1994 represents the genocide in Rwanda. In general the annual figure is between 5000 and 10.000, and refers often to sadistic killings by warring parties. The historical pattern is fluctuating much less than the pattern for battle-related deaths, but the annual figures are showing a downward trend just like battle-related deaths. An important insight is that the estimated total of 635.000 of civilians wilfully killed in civil wars 1989-2007 is in general - but far from always - a small fraction of those killed in during the course of military battles, which in turn are a small fraction of the indirect war deaths or indirect deaths due to G/P. Thus, a halt to the direct violence against civilians in the DRC and Darfur would make a large contribution towards reducing the much larger number of indirect deaths.

Important to note is that, and excluding the Rwandan genocide, data show that armed groups were responsible for almost 60% of the very conservatively estimated 135.000 intentional direct killings of civilians in civil conflicts. An extreme case is the conflict patterns in North and South Kivu, the DRC, from 2004 to September 2009, where rebel forces have been estimated to be responsible for almost 80% of all atrocities[5]. Not counting the Rwandan genocide, this means that during the past almost 20 years, it is not governments but rebels that carry out the majority of atrocities against civilians in civil conflicts. Nevertheless, some rebel movements are proxies for - or supported by - governments inside or outside the country in question. The role of governments in atrocities could thus also be indirect and larger than the above ratio suggests.

Figure II provides a pretty smooth line that indicates a stable rate of killings. This is partly caused by the use of annually aggregated data, which smoothens monthly variations. Figure III below, which builds on monthly aggregated data for North and South Kivu, the DRC, from 2004 to September 2009 illustrates the extent of the variation. Instead of a stable rate, there are extreme fluctuations, with bursts of killings followed by an almost a total absence of killings. The pattern appears to indicate a tit-for-tat pattern, in that that the violence is not easily explained by some simple mass atrocity policy from the parties involved, but rather that the parties appear to respond to, or are triggered by some sort of local circumstances or events: if the parties were bent on constantly killing civilians as part of some master plan, then the line should have been smoother, more consistent, as well as much higher. Moreover, data show that the atrocities are not carried out in the same locations, but instead move from one location to another. This implies that the international community can in theory do something about the violence, by influencing the local circumstances or deal with the local triggers. The issue of the causes of atrocities will be returned to later in the paper.


Number of Civilians Massacred in North and South Kivu, 2004-2009

A final insight is that whereas in general fewer individuals are killed wilfully than by crossfire, and while G/Ps are rare, the impact on post-conflict health is more negative and hence necessary to add to final casualty estimates as well as decisions to intervene. Hoddie & Smith (2009) report that the magnitude of atrocities (carried out by governments) in terms of G/P is a more robust predictor of post-conflict health (disability and death) than the magnitude of crossfire killings. One alleged reason is that G/P involves the murder of professionals (e.g., health care staff) and the destruction of human capital that serve important functions throughout societies. Another alleged reason is the large displacements of entire populations, which in turn loose access to healthcare and live under difficult conditions (incl. the spread of diseases, hunger, and lack of access to health care facilities). A third alleged reason is the destruction of social capital (e.g., trust) that in turn decreases the possibility of individuals to receive help through friends and contact networks. G/Ps and atrocities against civilians will thus continue to cause fatalities and worsened quality of life long after G/Ps have ceased to a larger extent than civil wars in general.

The Causes of Atrocities

After the path breaking study by Harff (2003), the number of statistical studies trying to account for the onset, occurrence or magnitude of G/P, or the more general phenomenon of mass killings of civilians, has finally started to accumulate.[6] Some of the studies focus on slow-moving country characteristics that serve as underlying causes or risk factors and are difficult for the international community to address in the short-term. Other studies focus on conflict characteristics that constitute immediate causes or triggers, some of which are in theory possible to influence in the immediate term.

In the context of civil wars, atrocities that are not genocidal in their goals are often claimed to be carried out for rational reasons, e.g., promote ethnic cohesion, secure access to resources, deter civilians from supporting the other warring party, forcibly recruit soldiers, or improve bargaining positions and counter military setbacks (cf. Valentino, Huth & Balch-Lindsay 2004; Kathman & Wood 2009; Wood 2010).  Atrocities are thus a symptom of military weakness, inability to provide other incentives (such as providing public services, or security) or lack of public support in militarily contested areas (Ibid.). Meanwhile, when rebels enjoy broad support and/or can provide public services, rebel atrocities serve no rational purpose, and may instead undermine public support and in extension strengthen opposing warring parties. Whereas government forces usually have some form of logistics and financial resources, rebels are dependent on civilians for, e.g., material resources, food, information and sanctuary (Ibid). This explanation describes accurately the situation in North and South Kivu, where civilians are "punished" and join rebel groups - or do not oppose them - out of fear. Rebels can often only offer life or death.

Since rebels are more exposed than government forces and more reliant on civilians, they should thus be more prone to resort to the atrocities when their position is weak or weakening. This expectation is born out in the overall pattern of atrocities against civilians reported above, in that rebels are overall responsible for 3/5 of all civilians murdered in civil wars, and for almost 4/5 in the case of the South and North Kivu. However, when rebels become very weak compared to government forces, atrocities may not increase recruitment, as the risk for retribution from government forces is larger than the risk for atrocities against civilians that refuse to be recruited or cooperate (Ibid.). 

These insights have been confirmed in a couple of recent statistical studies. Wood (2010) covering all civil wars 1989-2004 reports that the smaller the relative rebel capability, the larger the magnitude of atrocities against civilians; when governments increase the level of violence against civilians, so do rebels, and in particular weak ones. These findings are consistent with the ones reported in a study of the Vietnam War (Kalyvas & Kocher 2009). In this war, the insurgent side was highly disciplined (but also not militarily weak), and resorted almost only to discriminate and targeted violence against carefully identified individual government (South Vietnam) collaborators.

An interesting qualification of these findings, but exposed to the caveat of building on just one case, can be found in statistical study by Humphreys & Weinstein (2006) that focuses not on killings but on rape, amputations, theft, etc., by rebels in Sierra Leone. It reports that poverty, co-ethnicity, social ties, local military dominance, among other factors, did not prove statistically significant. Meanwhile, unit discipline in terms of punishment for bad behaviour against fellow rebels as well as civilians strongly influenced the risk for abuse: when unit discipline was low, the risk for abuse increased sharply. Hence, and applying to rebels, lack of group discipline makes rebels even more likely to kill civilians.

Similar to this, and concerning government forces, Valentino, Huth & Lindsay (2004) report that rebel support and military threats against governments increase the risk for government atrocities, which are seen as a government strategy: when the government is losing ground, the risk increases. A similar finding is reported in a study of the Spanish Civil War (Herreros & Criado 2009). Parallel to this, and referring to the Vietnam War, Kalyvas & Kocher (2009) report that indiscriminate bombings and shelling by government forces took place mainly in contested areas, that is, where the parties were under pressure from opposing forces.

The Track Record of Peacekeeping

During the past 20 years a number of UN led as well as non-UN led peacekeeping operations (PKOs) have repeatedly and to different extents attempted to address war induced humanitarian crises (genocide, starvation, mass atrocities, etc.) arising during the course of an operation. UN mandates commonly involve the protection of/support to civilians - either directly, or through the protection of relief operations or NGOs, but the enforcement elements are usually weak, and seldom involve the proactive use of force.

Do atrocities against civilians increase the willingness of the UN to deploy such operations, as demanded by the concept of R2P? The question of the conditions under which peacekeeping operations are established has been discussed from many perspectives, as summed up by Gilligan & Stedman (2003). Some scholars stress major powers' interests and "imperialistic motives", and it has in this tradition been claimed that UN operations are established in countries where the permanent members of the UN Security Council have national interest or major powers have raw material interests. Other approaches emphasize an interest in establishing democratic regimes as a motivating factor. Another major strand of thought claims that it is not outside countries' interests that are important, but rather the needs - in terms of war casualties and conflict durability - of the war-torn countries, and thus altruism rather than egoism on the part of the great powers. Still other approaches highlight the alleged importance of, e.g., a "CNN effect", the presence of a peace agreement, type of conflict, and the number of warring parties.

The statistical studies on the topic are recent and rare, but point in the same direction. Gilligan & Stedman (2003) examine the conditions under which the UN deploys PKOs in civil wars. For civil wars active after 1988, the study finds among other things a positive relationship between on the one hand civil war duration and number of casualties (battle-related, indirect and direct deaths), and on the other hand the probability of a UN operation. This finding supports the argument that needs conditions UN decisions. Mullenbach (2005) reports partly similar findings. Related to this, Hultman (2009) reports that violence directed against civilians by governments in civil wars increases the likelihood of UN PKOs. A similar impact by violence committed by rebel groups is reported, but only provided that the country is a so-called failed state. Meanwhile, no effect of civilian casualties is found on the likelihood of the occurrence the non-UN PKOs. This does not mean that non-UN PKOs have never been deployed because of atrocities, but only that there is no such overall trend. Another finding is that atrocities against civilians increase the likelihood that UN PKOs are given protection and robust mandates. Since the studies employ different data, research designs and statistical techniques, it is difficult to compare the findings in a straightforward manner. But at the very least, there are no statistical studies indicating that the UN tends to select the easy cases.

A natural follow-up question is whether these operations had the intended effect. Krain (2005) looks at ongoing G/P and attempts to predict their magnitude for the period 1955 to 1997. In contrast to impartial interventions, anti-perpetrator/biased interventions are reported to matter in a positive manner regardless of size. As Krain notes, the UN was always impartial during the period studied, and that makes it impossible to assess whether it can halt G/P should it be given a robust anti-perpetrator mandate that involves siding with one of the warring parties. Another challenge for assessing the general impact of UN operations is that the UN seldom intervenes before - or during - civil wars, even when violence is anticipated. Meanwhile, after civil wars, the risk for G/P is historically almost absent. This means that up to 1997 there were few examples in history where UN operations have been faced with ongoing large-scale atrocities.

Hultman (2010) focuses on ongoing civil wars and the narrower category of atrocities against civilians. It is reported that UN PKOs are in general associated with no impact, or even higher magnitudes of violence by governments and rebels. Meanwhile, UN PKOs with protection mandates decrease violence carried out by rebels as well as governments. Robust mandates are reported as having no impact. Kathman & Wood (2009) focus on the magnitude of regime sponsored mass killings only for the period 1995-2005, regardless of whether they took place in the context of civil wars. Anti-perpetrator as well as neutral military interventions, such as PKOs, increase the magnitude of killings in the short-run (indicating that the government is trying to "finish the job" [Ibid.] before it becomes impossible), but only neutral interventions decrease the magnitude in the long run.

These studies are important contributions, but the findings should be regarded as tentative, and should be replicated with other model specifications, and other lists for non-UN PKOs. For instance, the studies rely on country-level data. There is then no control over whether PKOs deployed close or far away from the rebel groups and the violence, and thus whether an impact is reasonable to expect and straightforward to explain. This means that we do not know exactly how this relationship should be explained and understood. In addition, there is no control for whether robustness or protection mandates of non-UN PKOs have any effect. As noted above, the patterns of violence in North and South Kivu suggest also that the causes are very much locally oriented. This means in turn that an analysis of the impact of PKOs needs to rely on local level rather than country level data to properly assess the impact of PKOs.

Meanwhile, few of the operations in these studies were initially deployed for the sole purpose (cf. Roberts 2006; Seybolt 2008; European Union 2009; United Nations 2009; Center on International Cooperation 2007, 2008, 2009) of protecting civilians, and even fewer used force reactively or proactively to halt G/Ps or atrocities. Among the UN operations, two stand out in terms of their robust methods for addressing G/P and atrocities carried out by armed groups. First is the United Nations Protection Force (UNPROFOR) in Bosnia that established protected zones, delivered humanitarian aid, and on occasions used force beyond self-defence. The second prominent example is the United Nations Mission in the Democratic Republic of Congo (MONUC), which may be said to be at the front line of the practice of robust pro-active use of armed force by UN operations against armed groups spoiling the peace and/or committing atrocities. MONUC has also since 2007 provided training (initially) to logistical support (food and fuel) and later also tactical support/joint operations (intelligence, medical evacuation, air strikes, joint patrols, fire support, and planning) to the DRC army in its war against rebels that have committed severe atrocities (Human Rights Watch 2009).

However, no UN operation has so far been initially deployed for the stated primary task of protecting civilians from genocide or atrocities, and has used force beyond self-defence to achieve those goals. Close cases include the African Union/United Nations Hybrid Operation in Darfur (UNAMID) deployed in 2007 as a successor to the African Union Mission in Sudan (AMIS) that had been deployed since 2004. While having a focus on protecting civilians from human rights abuses, it has not developed a robust practice of using force reactively or pro-actively. A similar case is the related United Nations Mission in the Central African Republic and Chad (MINURCAT) deployed in 2007 in the border areas of Chad, Sudan and the Central African Republic to deal with spillover effects from the Darfur conflict.

In contrast, multilateral non-UN interventions deployed primarily and initially to halt G/P and atrocities are rather common (Roberts 2006; Heldt & Wallensteen 2007; Heldt 2008; Seybolt 2008, European Union 2009; United Nations 2009; Center on International Cooperation 2007, 2008, 2009), and by early 2009 they included:

-  Operation Uphold Democracy, Haiti 1994

-  NATO's invasion of Kosovo, 1999

-  The International Force for East Timor (INTERFET), 1999

-  The EU Military Operation in the Democratic Republic of Congo (EUFOR DRC/Artemis), 2003

-  The Regional Assistance Mission to the Solomon Islands (RAMSI), 2003

-  The Multinational Interim Force in Haiti (MIFH), 2004

-  The EU Military Operation in Eastern Chad and North Eastern Central African Republic  (EUFOR Tchad/RCA), 2008

With the exception of Kosovo and Haiti, these interventions were aimed at non-governmental actors, though in the cases of Timor and Darfur, they targeted non-governmental actors that were seen as government proxies. Only the Kosovo operation and RAMSI were not initially authorised by the UN Security Council, and apart from the EUFOR operations in the DRC and Darfur, all were successful in ending atrocities and armed conflict. Perhaps not surprising, the successful interventions were large and overwhelming, and confined to small countries (Haiti, Kosovo, Timor, Solomon Islands), which is also where this kind of operations in general were carried out. EUFOR DRC/Artemis and EUFOR Tchad/RCA were meanwhile local protections forces, and the EUFOR DRC/Artemis was very localized in its deployment. Another observation is that none of the operations allied themselves with any of the warring parties, and all operations were either followed by PKOs (Haiti, Kosovo, Timor), developed into PKOs (Kosovo, Solomon Islands), or were PKOs from the very beginning (Darfur, the DRC). The insight offered from the non-UN cases is that multilateral interventions have worked well when robust, impartial and applied to small countries/territories.

Final Reflections

The findings presented in this overview should be regarded as tentative and rerun for robustness checks with other model specifications, and other lists for non-UN PKOs. With these caveats in mind, and referring to atrocities that do not have genocidal goals, even if the option may appear tempting, or appear as the only available option, data suggest that the proper strategy for PKOs in general in ongoing civil wars is not to carry out anti-perpetrator interventions that involve siding with one of the warring parties. If rebels are perpetrators, and they are weak, data suggest that anti-perpetrator interventions or continued and escalated warfare will motivate them to escalate violence against civilians if they are loosing (or fear loosing) territory to the other warring party.

Regardless of how difficult, naive and non-innovative it may appear, data suggest that the goal should be to create cease-fires (even localized ones), and in addition provide support to, and protection of, civilians. Historically such PKOs have decreased incentives for rebels to commit atrocities, since government forces are no longer considered an acute threat and territory is not being lost or threatened. It may also provide a breathing space for an unavoidable political solution to develop and for third parties to pursue diplomatic options. Data suggest also that peacekeepers may act robustly in impartially implementing a mandate to protect civilians, but should avoid siding with any of the warring parties. History then suggests that there is no need for the UN to change the impartial manner in which PKOs have been carried out in the past, but there are options in terms of robustness and the creation of safe zones that need to be explored further. Just as it is not a viable strategy for PKOs to enter into joint operations with warring parties, neither is it a viable strategy to act as a neutral bystander in the face of mass atrocities.

If the interventions are directed against governments involved in genocides, statistical data and examples like Kosovo, Rwanda and East Timor indicate that governments tend to escalate the violence in order to be "finish the job" before further killings become impossible to carry out. However, if governments have genocidal goals, it raises the question of whether these civilians may have been killed anyway, albeit at a slower rate, in the absence of an intervention. From that perspective, government run genocides are more difficult to deal with than non-genocidal atrocities by rebels and governments alike, and may need to involve a different toolbox for peacekeepers, or may not involve peacekeeping forces at all but rather other kinds of intervention forces. However, data suggest that neutral interventions also in these kinds of cases have the most beneficial long-term prognosis for reducing G/P.

On a final note, statistical research on the topic is in its infancy. At this point data indicates that it is important to carry out analysis with local level data instead of country level data in order to better account for the dynamics of atrocities, and to be able to understand the causal processes behind the local impact of PKOs. This means in turn that a new research agenda needs to be established and new data collection efforts need to be initiated in order for this area of research to progress and deliver insights of value to policy planners at the strategic level and to field staff at the tactical level.


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[1] By "armed conflict" is meant organized armed violence between two governments, or one government and one non-governmental party, over the issues of government or territory, that has incurred at least 25 casualties in a single year (Harbom & Wallensteen, 2009). Genocides and politicides refer to "The promotion, execution, and/or implied consent of sustained policies by governing elites or their agents - or, in the case of civil wars, either of the contending authorities - that are intended to destroy, in whole or part, communal, political or politicized ethnic groups" (Harff 2003: 58).

[2] Conflict data are from the UCDP/PRIO Armed Conflict Dataset v.4-2009 at G/P data is from Harff (2007).

[3] Battle-death data are from The Battle-Deaths Dataset (version 3.0), Lacina & Gleditsch (2005). Atrocities data are from the UCDP One-Sided Violence Dataset (version 1.3) 1989-2007. In contrast to estimates of armed conflicts, estimates of war casualties are controversial and difficult (cf. Lacina & Gleditsch 2005; Lacina et al. 2006; Spagat et al. 2009; Human Security Report 2010), and depend on whether only direct military and civilian battle deaths, or also indirect civilian deaths, should be included. Whereas the latter kind of direct casualties are very difficult to estimate, it is even more difficult to estimate indirect deaths as due to diseases and intentional/unintentional starvation, displacement, etc.

[4] For an overview one of the controversies, see See also Spagat et al (2009) and Human Security Report (2010) available for download at

[5] Raw data for 2004-2008 are from the Uppsala Conflict Data Project by kind permission. Data for 2009 are from Human Rights Watch (2009).

[6] See Valentino, Huth & Lindsay (2004), Besançon (2005), Krain (2005), Easterly, Gatti & Kurlat (2006), Humphreys & Weinstein (2006), Eck & Hultman (2007), Bae & Ott (2008), Colaresi & Carey (2008), Bundervoet (2009), Hoddie & Smith (2009), Kathman & Wood (2009), Querido (2009), Esteban, Morelli & Rohner (2010), Wayman & Tago (2010) and Wood (2010).

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