Introduction
In October 2015, The Intercept published the investigative report “The Drone Papers,” revealing the U.S. military’s drone program during the Obama administration, focusing on operations in Afghanistan, Yemen, and Somalia between 2011 and 2013 (Scahill et al., 2015). The inquiry uncovered intelligence errors in the selection targeting process, revealing that 90% of people killed were not the intended targets. While drone operations have proven effective for terrorist targeting and leader decapitation, they have also been highly problematic, increasing civilian casualties. Legally, the “Direct Participation to Hostilities” (DPH) condition and the “Continuous Combat Function” (CCF) are central mechanisms in the targeting process (Geneva Convention IV, 1949; ICRC, 2009).
This article analyzes the insufficiencies of CCF as central concerns in global security law practices for identifying terrorist threats, addressing the following research question: Why is current CCF deficient, and how can it be implemented to prevent civilian casualties? The article argues that CCF is inherently flawed – particularly through linguistic indeterminacy and intelligence failures – placing civilians at risk. Additionally, the CCF test should be revisited to balance two crucial considerations: extending the scope of targeting terrorist group members beyond active hostilities within both IACs and NIACs, while maintaining a higher threshold of civilian protection.
Central Legal Frameworks on Target Selection
Principle of Distinction & Direct Participation in Hostilities
The interpretation of the sources of International Humanitarian Law (IHL), specifically the Geneva Conventions (1949), the Additional Protocols (1977), and the Hague Regulations (1899; 1907), is guided by core principles. The Principle of Distinction is the operative principle here, affirming that “belligerents shall at all times distinguish between the civilian population and combatants and between civilian objects and military objectives” (ICRC, 2009).
Lubell and Derejko (2013) examine the geographical limitations of armed conflicts, highlighting the different approaches and risks in civilian protection. In IACs, this principle distinguishes civilians from combatants, with the latter enjoying the “Privilege of the Combatant.” In NIACs, by contrast, the principle differentiates state armed forces and Direct Participants in Hostilities. The latter are civilians who become legitimate targets “as soon as and for such time as” they directly participate in hostilities. In this context, individuals do not enjoy the Privilege of the Combatant (Geneva Convention IV; 1949).
The nexus between DPH and civilian harm lies in the target selection process, which is based on three criteria: a threshold of harm; a direct causal link between the act and the harm; and the intentional cause of harm, in support of one party, to the detriment of the other (ICRC, 2009). The target selection process imposes significant constraints on the permissibility of signature strikes.
The French presence in the Sahel region in 2015, where multiple armed groups coexisted, illustrates the challenge of determining whether targeted individuals were direct participants, highlighting the practical impossibility of a legitimate and coherent classification exercise (Doukhan, 2024).
Continuous Combat Function
In 2009, the ICRC published the Interpretative Guidance on Direct Participation in Hostilities, introducing the concept of “Continuous Combat Function” (CCF). This concept requires “lasting integration” in an organized armed group, involving preparation, execution, or command of hostile acts. This means an individual can be targeted simply by virtue of their role, without having carried out a hostile act.
Under this guidance, the temporal scope widens, removing the “as soon as and for such time as” condition and encompassing the period preceding the hostile act. Assessments are based not on membership status, but on behavioral or circumstantial evidence indicating de facto “lasting integration” in an armed group. This guidance has shaped state practice and legitimized high-risk targeting through open-text norms (Mignot-Mahdavi, 2023). While target selection already occurs under DPH, the CCF test extends identification practices.
The Legal Failures of CCF in Civilian Protection
The Costs of War (Brown University, 2025), a project which tracks the human toll of drone violence during the global War on Terror, recorded 408,749 civilian deaths in Afghanistan, Pakistan, Iraq, Syria, and Yemen as a direct result of post-9/11 wars. The link between implementing security practices to target terrorist group members and protecting civilians risks being undermined by internal deficiencies and misinterpretation of legal frameworks.
The legal framework that constitutes CCF within the ICRC Interpretative Guidance poses serious risks to civilians. CCF increases civilian risk in two domains: it deviates from the goal of maintaining high-level civilian protection, and fails to account for the dangers of its practices. In the first case, the concept of “lasting integration” remains under-defined, risking over-inclusion of individuals not actively participating in hostilities (Hofmann, 2015; Watkin, 2010). This ambiguity produces social and psychological consequences for civilians, including communal fragmentation, depoliticization, psychological distress, and a sense of “self-objectification,” as drone violence is perceived as a form of psychological colonization (Edney-Browne, 2019). The Obama administration’s intent to act within legal justification and IHL jurisdiction proves the instrumentalization of unclear definitions in the counterterrorism context, which is exemplified by Pakistani state consent at the height of the U.S drone programme (Boyle, 2015). In the context of signature strikes, this risk is amplified by the use of behavioral indicators (e.g., GPS location and quasi-membership status) and the extension of spatio-temporal targeting to ceremonies (Heller, 2013; Chamayou, 2015). Reliance on such information poses challenges in distinguishing legitimate targets from innocent civilians (Gregory, 2011). The CCF test focuses on function, excluding conduct that requires witnessed engagement in hostile acts (Mignot-Mahdavi, 2023).
In the second case, ignoring the risks associated with these practices threatens civilians. These errors not only illustrate issues of transparency and accountability, but also inefficiencies in compensation policies, failing to meet the financial and emotional losses of victims. The UN Report of the Special Rapporteur on Extrajudicial, Summary, or Arbitrary Executions has warned about the low threshold for lethal force, reliance on opaque intelligence, and the redefinition of combatancy in ways incompatible with IHL (Alson, 2010). These failures are illustrated by the 2017 U.S. strike on Al-Jinah Mosque in Aleppo, Syria, which targeted civilians without evidence of any military objectives, and the 2021 French strike in Bounty Village, Mali, on a civilian wedding (Human Rights Watch, 2017; UN News, 2021). In 2017, The New York Times revealed unaccounted-for civilian deaths in northern Iraq in the U.S.-led air campaigns (Khan and Gopal, 2017). Specifically, the 2009 U.S. strike on the Razzo family in Mosul, Iraq, misidentified civilians due to flawed and outdated intelligence. These cases provide empirical evidence that operationalizing the CCF test using behavioral and probabilistic data undermines civilian protection.
Practical Implications
Traditional legal debates have questioned whether the CCF test should extend beyond doctrinal boundaries, lowering the threshold to individuals in armed groups who do not meet the threshold for active participation in hostilities but are involved in terrorist activities (Henry, 2018). A clearer and narrower version of the CCF test has been proposed to prevent the expansion of targeting practices (Mignot-Mahdavi, 2023). This approach aims to balance extending the scope of targeting terrorist group members beyond active hostilities while maintaining robust civilian protection.
Implementation can occur across three domains: providing repeated evidence of direct engagement in violent acts, refining behavioral indicators of CCF, and establishing a higher evidentiary threshold when spatio-temporal targeting is extended. Pons (2018) proposes a new assessment framework for CCF, creating an objective threshold that separates combatant identification from the DPH test, balancing civilian protection under the Geneva Conventions and Additional Protocols with states’ counterterrorism flexibility. This framework clarifies the evaluation of operational planning, participation, and execution of hostile acts, ensuring that targetability is not automatically assumed based on behavior, functional role, or group association. For example, logistic or peripheral members of armed groups in Pakistan’s tribal areas (FATA) have historically been targeted based on function. Under a narrower CCF framework, targeting would require repeated and verified participation in attacks (Amnesty International, 2013).
Limitations of CCF Implementation and its Policy Implications
CCF implementation faces two core limitations. First, the epistemic limits of intelligence cannot fully eliminate uncertainty in CCF targeting (Watkin, 2010). Second, the non-binding nature of the ICRC Interpretative Guidance means that state resistance can limit in CCF implementation, while states may strategically benefit from ambiguity. For example, the politicization of global security law in contexts such as the Global Counter-Terrorism Forum reflects recurring patterns across similar security contexts (Rodiles and Sullivan, 2025).
From a policy perspective, mandatory legal assessments before strikes, such as an ex-ante legal review of signature strikes and a post-strike disclosure of the targeting rationale, particularly regarding criminal responsibility in AI-enabled defense systems, would enable a more precise and conscientious evaluation of the target-selection process (Klonowska, 2020). Furthermore, reaffirming the Principle of Distinction in assessing civilian status, in accordance with Article 50 of the Geneva Conventions Additional Protocol I, would allow for a more accurate interpretation of CCF (Additional Protocol I, 1977).
Conclusion
The post-9/11 War on Terror launched by the U.S. and the subsequent expansion of drone programs under the Obama administration were widely regarded as highly effective in targeting members of terrorist organizations. The civilian harm resulting from misidentification in attempts to target group members, however, has been unprecedented.
The explanation for these faulty practices lies in the interaction between technology and law, where the notion of co-production shapes the interpretations that allow such practices to persist. By situating CCF within the broader context of remote warfare and arguing that the CCF test is inherently flawed yet in need of reform, this article has evaluated how legal norms are operationalized through intelligence technologies that privilege behavioral deduction over conduct-verification. Debates on CCF test implementation remain critical from analytical and policy standpoints. Future research should focus on two domains: accountability mechanisms addressing harm caused by these practices, and the epistemic uncertainty surrounding intelligence oversight in the CCF test. Ultimately, while target selection processes to identify members of terrorist organizations remain central to security debates, it is imperative to foreground the minimization of civilian harm and suffering within this discourse.
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