In events with at least one Iraqi civilian victim, the methods that killed the most civilians per event were aerial bombings (17 per event), combined use of aerial and ground weapons (17 per event), and suicide bombers on foot (16 per event). Aerial bombs killed, on average, 9 more civilians per event than aerial missiles (17 vs. 8 per event). Indeed, if an aerial bomb killed civilians at all, it tended to kill many. It seems clear from these findings that to protect civilians from indiscriminate harm, as required by international humanitarian law (including the Geneva Conventions),4 military and civilian policies should prohibit aerial bombing in civilian areas unless it can be demonstrated — by monitoring of civilian casualties, for example — that civilians are being protected.
Suicide bombers in Iraq are mainly used strategically by sectarian or insurgent forces, with deployment at targets after apparently coordinated planning.5 Although the bomb's blast is undiscriminating, the individual bomber is not. A suicide bomber on foot acts as a precision weapon — a close-quarters "smart bomb" whose pattern of killing many civilians at a time can result only from either disregard for civilians when targeting opposition forces or direct targeting of civilians. When combatant forces intentionally target civilians, they commit a war crime and violate international humanitarian law pertaining to both international and civil armed conflicts.4
Among victims of known sex — that is, those identified as male or female, regardless of age — the proportion of female civilians killed varied according to the weapon used, as did the proportion of children killed among victims of known age. Because the media may tend to specifically identify female and young victims more readily than male adults among the dead, which could inflate our findings for the percentages of female civilians and children killed, these findings should not be considered absolute proportions; they are, however, relatively robust indicators of the varying demographic characteristics of civilians killed by different weapons. Female Iraqis and Iraqi children constituted the highest proportions of civilian victims when the methods of violence involved indiscriminate weapons fired from a distance: air attacks and mortars. That air attacks, whether involving bombs or missiles, killed relatively high proportions of female civilians and children is additional evidence in support of the argument that these weapons, like mortars, should not be directed at civilian areas because of their indiscriminate nature.
By contrast, the methods that resulted in the highest proportions of male civilians among victims of known sex were the relatively close-quarter, precise methods of gunfire (91% male civilians), execution (95% male civilians), and execution with torture (97% male civilians). Execution with torture, the most intimate, brutal method of killing, was used the most selectively against male (rather than female) civilians and against adults (rather than children). By nature, execution is precise and deliberate — the highly controlled, usually planned killing of a captured person. The character of this form of killing, combined with our findings that a great many civilians were killed by execution, in many events, with strong selection according to the sex and age of potential victims, supports the assessment that executions have been applied systematically and strategically to civilians in Iraq.5Certainly, different perpetrators can use similar weapons in different ways, with different effects on civilians. Nevertheless, our findings regarding the rates of Iraqi civilian death resulting from different types of weapons reveal stark differences in the effects of various weapons on civilians, in terms of both the numbers and the demographic characteristics of those killed. Weapons that kill relatively high proportions of Iraqi civilians, female civilians, or children are particularly hazardous to public health. Such indiscriminate or intentional effects from armed conflict must be radically curtailed to comply with international humanitarian law.4 We believe that all combatant forces and governments should implement policies of routine and transparent collection and release of verifiable data on the civilian casualties of military actions. Such monitoring would facilitate timely reparative action and must inform planning if armed combat is to be prevented — as much as possible — from harming noncombatants. Policymakers, war strategists of all persuasions, and the groups and societies that support them bear moral and legal responsibility for the effects that particular combat tactics have on civilians, including the weapons used near and among them. Sources: The Weapons That Kill Civilians — Deaths of Children and Noncombatants in Iraq, 2003–2008 Madelyn Hsiao-Rei Hicks, M.D., M.R.C.Psych., Hamit Dardagan, Gabriela Guerrero Serdán, M.A., Peter M. Bagnall, M.Res., John A. Sloboda, Ph.D., F.B.A., and Michael Spagat, Ph.D. Endnotes: 1. Coupland R. Security, insecurity and health. Bull World Health Organ 2007;85:181-184. 2. Iraq Body Count home page. (Accessed March 27, 2009, at http://www.iraqbodycount.org.) 3. Iraq Family Health Survey Study Group. Violence-related mortality in Iraq from 2002 to 2006. N Engl J Med 2008;358:484-493. 4. Hicks MH, Spagat M. The Dirty War Index: a public health and human rights tool for examining and monitoring armed conflict outcomes. PLoS Med 2008;5:e243-e243. 5. Hafez MM. Suicide terrorism in Iraq: a preliminary assessment of the quantitative data and documentary evidence. Stud Conflict Terrorism 2006;29:591-619.