Direct participation in hostilities

== Definition ==
Direct participation in hostilities
Civilians benefit from a general protection from attack.Art. 51 (2) AP I; ICRC, CIHL Study, Rule 1, 7 and 25. However, this protection is lifted “for such time as they take a direct part in hostilities”.Art. 51 (3) AP I; ICRC, CIHL Study, Rules 6 and 34. During this period, a civilian who directly participates in hostilities (DPH) may be attacked lawfully.ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009)69-73; •	Hans-Peter Gasser/ and Knut Dörmann, ´Protection of Civilian Population´ in D Fleck (ed), The Handbook of International Humanitarian Law (3rd edn, OUP 2013) 255-257. As customary international law,ICRC, CIHL Study, Rule 6. this rule also applies to cyber operations, when these occur during an armed conflict.Tallinn Manual 2.0, Rule 97.
Absent a definition, it remains controversial when a conduct qualifies as direct participationProgram on Humanitarian Policy and Conflict Research at Harvard University, Commentary on the HPCR Manual on the International Law Applicable to Air and Missile Warfare (hereinafter AMW Manual) (2009) Rule 28, 119-120; ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 67; Michael N. Schmitt, ´The Interpretive Guidance on the Notion of Direct Participation in Hostilities: A Critical Analysis´, Harvard National Security Journal (2010) 25. and how long this period lasts.ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 41, 65-68; Tassilo Singer, ´Update to Revolving Door 2.0 – the Extension of the Period for Direct Participation in Hostilities Due to Autonomous Cyber Weapons´ in H. Roigas, R. Jakschis, L. Lindström and T. Minarik (eds.), Defending the Core, 9th International Conference on Cyber Conflict 2017 (NATO CCDCOE Publications 2017), 121-133; Bill Boothby, ‘“And for such time as”: The time dimension to direct participation in hostilities’ (2010) 42 International Law and Politics 741. According to the ICRC DPH study,ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 46-64. a specific act must meet the following criteria to qualify as direct participation in hostilities:
# the act must be likely to adversely affect the military operations or military capacity of a party to an armed conflict or, alternatively, to inflict death, injury, or destruction on persons or objects protected against direct attack (threshold of harm), and
# there must be a direct causal link between the act and the harm likely to result either from that act, or from a coordinated military operation of which that act constitutes an integral part (direct causation), and
# the act must be specifically designed to directly cause the required threshold of harm in support of a party to the conflict and to the detriment of another (belligerent nexus).ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 46.
These criteria are neutral as to the means and methods of warfare used by the act in question; accordingly, they equally apply to cyber operations.Tallinn Manual 2.0, commentary to Rule 97, para. 5. Arguably, “digital” damage is included as long as the cyber operation negatively affects the enemy’s military operations or military capacity.Tallinn Manual 2.0, commentary to Rule 97, para. 5; see also ICRC, 51; AMW Manual, commentary accompanying Rule 29. Examples of direct participation in hostilities through cyber means include damaging enemy property or equipment, or the transmission of military information for immediate use by a belligerent. 
Additionally, in a NIAC, a person who is a member of an organized armed group (OAG) that is a party to the conflict loses his or her protection if he or she fulfils a continuous combat function (CCF) within the group. This occurs when the (continuous) function of a person in a group is to directly participate in hostilities. It requires lasting integration into the OAG in question.ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 33-35; Crit.: Michael N. Schmitt, ´The Interpretive Guidance on the Notion of Direct Participation in Hostilities: A Critical Analysis´, Harvard National Security Journal (2010) 21-24. This includes the individuals whose continuous function involves the preparation, execution or command of cyber operations amounting to DPH.ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 34. Simple membership in a hacker group without any DPH function does not suffice for a CCF,ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 33-35. as the DPH criteria are designed to exclude subsidiary support functions within a group.Emily Crawford, ´Virtual Battlegrounds: Direct Participation in Cyber Warfare´ ( I/S: A Journal of Law and Policy Vol. 9:1 2013)12; Crit.: Yoram Dinstein (ed), Non-International Armed Conflicts (CUP 2014), 61-62.
 
The CCF concerns the temporal scope of the loss of protection and is function-based.ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 45, 70 The membership in an OAG starts when the civilian “starts de facto to assume the continuous combat function” and lasts until that function ceases.ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law (ICRC 2009) 72. 
Publicly available national positions that address this issue include:
 (2019), 
 (2021), 
 (2021).
==National positions==
===France (2019)===
===Germany (2021)===
===United Kingdom (2021)===
== Appendixes ==
=== See also ===
* Scenario 18: Legal status of cyber operators during armed conflict
=== Notes and references ===
=== Bibliography and further reading ===
Category:Direct participation in hostilities
Category:International humanitarian law
Category:Legal concepts