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The U.S. Practice of Collateral Damage Estimation and Mitigation
Pepperdine Working Paper (2011)
  • Greg McNeal, Pepperdine University
This paper explains how the U.S. military estimates and mitigates the impact of conventional weapons on collateral persons and objects in most military operations involving air-to-surface weapons and artillery. It is the descriptive part of a larger work discussing the normative implications of U.S. targeting practices. In recent years, an entire body of academic literature and policy commentary has been based on an incomplete understanding of how the U.S. conducts military operations. The literature is incomplete because U.S. practices are shrouded in secrecy and largely inaccessible. As a result commentators have lacked a descriptive foundation to analyze and critique U.S. operations. Their writings have focused on easily describable issues such as whether a target was a lawful military objective, and then typically shift attention to the question of proportionality balancing and collateral damage. These commentators skip an important aspect of actual practice - the scientifically grounded mitigation steps followed by U.S. armed forces. Those mitigation steps are designed to ensure a less than 10% probability of collateral damage resulting from any pre-planned operation. This paper’s description differs from the general and incomplete approach currently found in scholarship and more accurately describes the reality of modern operations. In those operations U.S. armed forces follow rigorous steps prior to engaging in any proportionality balancing. This paper is intentionally descriptive and explanatory; it makes a contribution to theory by providing a qualitative empirical account (based on public documents and field interviews) that explains for the first time in scholarly literature the process of collateral damage estimation and mitigation as practiced by the U.S. military. While this paper will be especially useful for those seeking to understand how collateral damage is estimated in targeted killing operations, the paper’s relevance is not limited to the context of targeted killings. Key Findings: In pre-planned operations the U.S. military follows a rigorous collateral damage estimation process based on a progressively refined analysis of intelligence, weapon effects, and other information. When followed, this process dramatically reduces the amount of collateral damage in U.S. military operations, and also ensures high levels of political accountability. However, due to the realities of combat operations, the process cannot always be followed The U.S. military’s collateral damage estimation process is intended to ensure that there will be a less than 10 percent probability of serious or lethal wounds to non-combatants Less than 1% of pre-planned operations which followed the collateral damage estimation process resulted in collateral damage When collateral damage has occurred, 70% of the time it was due to failed “positive identification” of a target. 22% of the time it was attributable to weapons malfunction, and a mere 8% of the time it was attributable to proportionality balancing - e.g. a conscious decision that anticipated military advantage outweighed collateral damage According to public statements made by U.S. government officials the President of the United States or the Secretary of Defense must approve any pre-planned ISAF strike where 1 civilian casualty or greater is expected.
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Citation Information
Greg McNeal. "The U.S. Practice of Collateral Damage Estimation and Mitigation" Pepperdine Working Paper (2011)
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