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Post-2015 Consensus: Conflict and Violence Assessment, Hoeffler Fearon

There is an ongoing debate on what brought about the reduction in violence over the past three decades in high income countries but the phenomenon cannot be reduced to the application of a few societal programs. Attitudes to violence typically change slowly over time; examples are wife beating and corporal punishment of children. Programs aimed at reducing violence are thus unlikely to produce results quickly. In addition many programs have not been set up in a manner allowing rigorous evaluation. For many of these interventions we neither know their impact nor do we know their costs, thus making it impossible to provide BCRs. 

Despite the uncertainty of what feasible targets for violence reduction are and how they can be achieved we advocate the inclusion of such targets in the post-2015 agenda. Our estimates suggest that the costs of violence are high; the welfare cost of collective, interpersonal violence, harsh child discipline, intimate partner violence and sexual abuse are equivalent to around 11 per cent of global GDP. The cost of homicides are much larger than the cost of civil conflict. However, violence perpetrated in the home appears to be the most prevalent form of violence. Domestic abuse of women and children should no longer be regarded as a private matter but a public health concern.

Summary of the most high-yielding targets from the paper

Conflict and Violence Targets Benefit for Every Dollar Spent
Reduce Assaults. $17
Eliminate severe physical violence as a method of child discipline. $11
By 2030, reduce the number of countries experiencing large scale wars (1000+ deaths) to 3 or fewer and the
number of countries experiencing small scale wars (>1000 deaths) to 14.
Improve Policing. Likely To Be High
Eliminate all forms of violence against women and girls. Likely To Be High

Summary of Cost Estimates


In the broad area of building stable and peaceful societies, the UN HLP has identified several areas where the benefit/cost ratio may be very high, and that have been relatively neglected by the development community to date.  There are areas where the current economic and social costs are plausibly quite large, and where the amount of attention is very small in comparison to other areas such as health, education, and governance reform.  We argue that there is a strong case for making societal violence reduction a priority in the post-2015 Sustainable Development Goals. 

When thinking about the costs of violence, the international community has focussed primarily on civil wars. However the main impacts of civil war are concentrated in a small number of countries, and policy instruments for reducing the major negative effects are distinctly limited. In contrast, for every civil war battlefield death, roughly nine people – 7% of whom are children – are killed in interpersonal disputes. Thus, physical violence is much larger and more pervasive than civil wars alone.

The direct economic costs of this are very large and increased still further if social damage and individual suffering are included, and yet a tiny fraction of aid funding goes towards reducing societal violence or improving criminal justice systems. Because the area receives so little attention, it is impossible to estimate a rate of return for projects aimed at reducing violence, but it is plausible that returns are substantially higher for this than for projects aimed to improve governance.

Although the goal of eliminating violence against women and children by 2030 as advocated by the UN HLP must be seen as purely aspirational, substantial reductions can be made as falling homicide rates in high-income countries in general and also in Colombia have shown. Maintaining an annual reduction of 1.5% – half the average seen in these examples – would reduce the global homicide rate by 21% by 2030. Halving the current high level of intimate partner violence would dramatically improve the welfare of millions of women and help break ongoing cycles of violence.

Interpersonal and collective violence

According to UNODC figures, in 2008 there were just over 418,000 homicides in the 186 countries with data.  In that same year, about 49,000 people are estimated to have died in “battle deaths” in civil wars.  Civil wars can cause wholesale destruction and displace communities, but recently only 20-25 countries have been affected each year, generally involving only a small part of the country. In contrast, about a third of countries had a homicide rate of over 10 per 100,000, considered to be an epidemic level by WHO.

A recent study estimated each homicide in the USA to cost $9.1 million, and this does not take account of effects on family and friends nor the dynamic economic effects of violent crime. Scaling this on the basis of each country’s GDP and their murder rate, the total cost varies from 0.33% of GDP for high income countries to 4.1% for Latin America and the Caribbean. Overall, this comes to 1.71% of global GDP for a single category of violent crime. These figures are an estimate of the benefits which could be achieved from a reduction in violence, not a current loss to the economy.

Other violent crimes, such as assault, are much more common, though less costly individually. A US study estimated total costs of violent crime in 2012 to be 2% of GDP, while the British Home Office estimated 6.1% for England and Wales in 2003. The higher figure in the UK is due in part to an assumed underreporting of actual crime. Developing country estimates are of a similar magnitude, although figures are less common and more conjectural.

Using 2013 figures from the Institute for Economics and Peace, interpersonal violence has a global welfare cost of 2.1% for an average country, or 1.44% if we weight by country population. In comparison, collective violence (dominated by civil war) has a cost of only 0.33% on average: less than one-sixth of the cost of interpersonal violence. The difference is actually even greater in most regions, but the civil conflicts arising from the Arab Spring raise the average collective violence estimates.

Violence against children

There is no universally accepted definition of what constitutes child abuse and neglect. For example, corporal punishment is common but what is regarded as excessive is a cultural issue. In some societies, for example Egypt, Somalia and Ethiopia, the majority of girls still undergo female genital mutilation (FGM). Overall, the global prevalence of violence against children is difficult to estimate because much abuse is never reported. And despite the media attention on such issues as FGM and child prostitution, most of the violence happens at home: 80% of all perpetrators are the child’s parents. We do not consider abuse and neglect in schools, care institutions, prison, at work and in the community since no comparable figures are available across countries.

WHO provides global data for children up to 14. Almost 34,000 deaths are attributed to interpersonal violence. The great majority of these occur in the first month of life, and girls are more at risk than boys (18 per 100,000 as against 14 per 100,000). However, the highest rate is for newborn girls in the East Asia Pacific region: 46 per 100,000. Beyond that, the rate drops to around 2 per 100,000 for both genders. For comparison, the highest overall homicide rate is for boys and men aged 15 to 29, at 19 per 100,000 (mainly driven by high rates in Latin America and the Caribbean and sub-Saharan Africa). Child homicides as a percentage of the total vary from 2 in Europe and Central Asia to 14 in the Middle East and North Africa, and we use these figures to estimate total costs. Using the same figure as that for an average homicide ($8.44 million), we estimate a total cost of $37.7bn, corresponding to 0.044% of world GDP.

We approximate the level of non-fatal child abuse through violent disciplinary practices from UNICEF data covering 34 countries (about 10% of children). Aggressive and violent punishment is common, and used by 73% of carers surveyed. Severe physical punishment is used by 28% of primary carers in the Middle East and North Africa and 24% in sub-Saharan Africa, but it is less common elsewhere. Using average regional rates for severe physical punishment, a total of about 290 million children (15.5% of the total) are abused in this way.  At a unit cost of $98,000, we estimate the total cost of child abuse as about $3.6 trillion, or 4.2% of global GDP. While this is about 1.9% of GDP in high income countries, it rises to nearly 19% in sub-Saharan Africa.

UNODC figures show 72,000 cases of child sexual assault and rape (almost a quarter of the total) but, based on surveys of women, it seems that this is just the tip of the iceberg, with significant adults in children’s lives most likely to be the abusers. Using a unit cost for all rape/sexual assault cases of $199,642 and considering only reported cases, the absolute minimum cost of child sex abuse is about $37 billion (0.043% of world GDP).

In the context of violence against children, it is sensible to highlight the practice of early marriage in some cultures. Marriage of emotionally and physiologically immature girls to older men, often against their will, has a number of health implications as well as a higher risk of violence and sexual abuse. For girls under 16 in Nigeria, Cameroon and Ethiopia the maternal mortality rates were found to be about six times higher than for mothers aged 20-24. 15% of all deaths for girls and women aged 10-24 are due to maternal conditions, the leading cause of deaths in this age group.

Early marriage is most prevalent in South Asia; in 2000, 56% of all young women were married before they were 18. However, while 41% of women aged 45-49 were married by age 15, only 15% of women in the 20-24 age range were married this young. This declining trend is the same for all regions. In the countries surveyed, 47% of all women aged 45-49 were married by the age of 18 in 2000. If the trend continues, this figure should be 25% in 2030.

Violence against women

Across the world there are a number of harmful traditional practices that constitute violence against women. Examples include female infanticide and prenatal sex selection, early marriage, dowry-related violence, female genital mutilation (FGM), “honour” crime, and maltreatment of widows. However, there is limited information on many of these practices, with the exception of FGM.

The most common form of violence experienced by women globally is intimate partner violence (IPV), with about 30% of women experiencing this in some form during their lifetime. WHO studies conclude that women suffering IPV are 16% more likely to have a low birth weight child and they also have a higher risk of contracting sexually transmitted diseases. There are also longer-term consequences for children of abused women: daughters are more likely to be abused by their partners and sons are more likely to become abusers themselves.

About 16% of all homicide victims are women of 15 and over; 43% of all female victims are killed by a current or former intimate partner. Using a standard unit cost of $8.44 million per homicide (which may be too high because women’s earnings are lower), the global cost of female homicides is estimated at around $105 billion, or 0.12% of GDP.

Overall prevalence of non-fatal violence against women is difficult to estimate, but there are figures available for sexual assault and rape. However, most cases are never reported. Much violence – sexual, physical and emotional – is perpetrated by intimate partners. Revealingly, over half of women in sub-Saharan Africa think their husbands are justified in beating them for such things as arguing or burning the food, while only 37% of men agreed that this would be acceptable.

The prevalence of IPV varies widely. Only 4% of women over 15 in high-income countries report it, compared to a high of 28% in sub-Saharan Africa. Assuming 90% of women have partners and using a cost of $95,023 for an assault (actually more than double this figure for rape and sexual assault) the total costs of IPV are $4.4 trillion, or 5.2% of global GDP. The figure for reported cases of sexual violence, whoever the perpetrator, is $67 billion, or 0.08% of global GDP, using a unit cost of $199,642. In both cases, the actual figure is likely to be much higher because of the high level of under-reporting.

FGM is still widespread in Africa and the Middle East. Although it is outlawed in 26 of 29 countries surveyed, UNICEF estimates that about 100 million women worldwide have undergone FGM and that 30 million girls are at risk over the coming decade. Amongst women aged 15-49 FGM is almost universal (88% or higher) in Somalia, Guinea, Djibouti, Egypt, Eritrea, Mali, Sierra Leone and Sudan, although in all countries the prevalence rates among girls aged 0-15 are lower than for their mothers. A WHO study shows that women who have undergone FGM suffer more obstetric problems, including higher rates of perinatal death.

Aid programs targeted at reducing violent crime or improving police and judicial system performance

Considerable amounts of aid are directed towards ‘fragile states’ to help stop or prevent civil war, and to emergency humanitarian aid, but violent crime, child abuse and domestic violence are far more pervasive and costly in terms of human welfare. There is, however, great wariness about providing aid to police and other security forces. Aid for government and civil society projects has risen sharply to 13.63% of the total since the end of the Cold War; within this larger category, legal and judicial aid has increased, but still only to about 1% of the total. Projects which have ‘crime prevention’ as one component receive in total only 0.27% of funding. The bulk of this goes to post-conflict countries and is not directly related to pre-existing levels of societal violence. Although it is very difficult to derive reliable figures for benefits of projects of this type, funding for peace-keeping operations and post-conflict aid does seem to be modestly cost-effective.

The return on investment in reducing civil war and societal violence

Wealthier regions tend to be characterised by lower rates of societal violence, so development is likely to decrease violence with time. In addition to social programs, one of the commonly suggested measures is to criminalize certain forms of violence, but this appears to have a limited effect when it runs counter to social norms. Also, studies on policy interventions have mainly been in high-income countries, where police and the criminal justice system have the institutional capability to be effective. In contrast, in many low-income countries, police corruption, abuse, and simple poor performance appear to be a large part of the problem of societal violence. 

In rich countries, targeting resources on ‘hot spots’ and using ‘problem-oriented policing’ appear to have a very low cost and their benefit-cost ratios are likely to be high. A similar approach could be very effective in developing countries where police and state authorities are interested in improving performance and where there is sufficient political will. Alcohol consumption is another contributory factor to violence and a number of cost-effective interventions to make drinking more responsible seem to be possible.

Turning to specific interventions, a number of programs have been assessed to reduce the level of violence against children. Early response of trained social service and welfare officers appear to provide the best BCR, at about 13-14. Home nurse visits to at risk mothers and newborns also offer a positive BCR, estimated at around 2.75. However, implementation could be difficult in low and middle income countries.

Programs to improve parenting skills can also be very cost effective. The best-known is the Positive Parenting Program, or ‘Triple P’, applied in a number of high and middle income countries. A two-year evaluation in the USA found that in a population of 100,000 children under 8 years of age there were 688 fewer cases of substantiated child maltreatment recorded by child protective services staff, 240 fewer out-of-home placements and 60 fewer children with injuries requiring hospitalization or emergency room treatment. This has a calculated BCR of 8.74.

On the question of FGM, legal reform appears to have little impact and there is no reliable evidence of other specific interventions lowering the prevalence. However, the incidence of FGM has declined in a number of countries with medium to low prevalence rates over the last 15 years; in contrast there has been little reduction in countries with high prevalence of the practice.

Interventions to combat domestic abuse such as the DASH (Domestic Abuse, Stalking and Honour-Based Violence) risk identification model in the UK and the Duluth model in the United States and elsewhere have not been properly evaluated in terms of their impact. Programs aimed at economic empowerment, such as (un)conditional cash transfers and micro-finance programs do not appear to systematically lower levels of violence, although a conditional cash transfer program in Ethiopia increased the chances of girls going to school threefold and reduced their chances of early marriage by 90%. Messages promoting the positive aspects of ‘doing the right thing’ have also been successful, but no BCRs are available for any of these interventions.


As of 2012, there were about 30 active civil conflicts ongoing in 25 countries. Although they account for a relatively small proportion of violent deaths, they can have massive indirect effects. But civil war is probably far less amenable to “treatment” by international aid programs or other policy interventions than are obstacles to development in areas like health and education.  So the idea of international targets for levels of civil war is necessarily going to be much more aspirational than operational. 

We have developed targets for wars of different intensity (‘small’ being 25-999 killed in combat in a given year) and different objectives (taking over central government of gaining more autonomy for a region). Given the downward trend, we propose a 2030 target of a 20% reduction from 2012 levels or a 20% reduction in the current trend, if this is larger. Total wars would decline modestly to 17.1 from the 2012 level of 20, but large-scale civil violence would be rare, at only three ongoing conflicts.

Evidence from the UK suggests that child homicides have been reduced by 40% over the last ten years. With 75% of all children being murdered by a member of their family, a friend or acquaintance, interventions should be targeted mainly at the family. If a reduction of 43% could be achieved by 2030, the number of neonatal deaths could be reduced by 745 annually and there would be 6,370 fewer deaths of children under 14. We propose a zero target for severe physical punishment, with the incidence of less violent punishment halving to 30%.

Given large reductions in the incidence of intimate partner violence in the USA, it is feasible to target a halving of the number of women experiencing this by 2030. We also suggest a target of no marriages before the age of 15. Because of the difficulties of reducing the number of young women suffering FGM in high-incidence countries, we suggest an aspirational target of a 50% reduction. In societies with lower incidence, an elimination of the practice seems feasible.


Civil war violence is too narrow a category when considering what the next set of international development goals concerned with violence should be.  Interpersonal violence in its major forms – homicide and violent assaults, including intimate partner violence, child abuse, and FGM – are far more pervasive than civil war violence and almost surely far more costly in terms of human welfare.  If it is the case that the benefit-cost ratio of interventions are at least comparable across these three areas (societal violence, civil war-related costs, and poor governance), then there is a strong case that much more aid should be flowing to programs to address violent crime and abuse.