Rule 46. Orders or Threats that No Quarter Will Be Given
Note: The duty to grant quarter is a basic rule that prohibits attacking a person recognized as hors de combat in combat situations on the battlefield. The treatment due to persons hors de combat is dealt with in Part V.
Rule 46. Ordering that no quarter will be given, threatening an adversary therewith or conducting hostilities on this basis is prohibited.
Summary
State practice establishes this rule as a norm of customary international law applicable in both international and non-international armed conflicts. While all those who take a direct part in hostilities must respect this rule, in practice it will be particularly relevant for commanders.
International armed conflicts
The prohibition on declaring that no quarter will be given is a long-standing rule of customary international law already recognized in the Lieber Code, the Brussels Declaration and the Oxford Manual and codified in the Hague Regulations.[1]  “Directions to give no quarter” was listed as a war crime in the Report of the Commission on Responsibility set up after the First World War.[2]  This rule is now set forth in Additional Protocol I.[3]  Under the Statute of the International Criminal Court, “declaring that no quarter will be given” is a war crime in international armed conflicts.[4] 
The prohibition is contained in numerous military manuals.[5]  Under the legislation of many States, it is an offence to issue an order that no quarter be given.[6]  In several cases after the First and Second World Wars, the accused were charged with violating this rule.[7] 
The inclusion in Additional Protocol I of the prohibition of “threats” to order that no quarter shall be given or to conduct hostilities on the basis that no quarter shall be given is uncontested and it is incorporated in numerous military manuals.[8]  The legislation of several States also includes it.[9]  The prohibition of threats that no quarter shall be given is supported by several States not, or not at the time, party to Additional Protocol I.[10]  The prohibition on threatening to carry out a prohibited act is generally recognized in international law. In addition, if it is prohibited to order or threaten that no quarter shall be given then, a fortiori, it is prohibited to carry out such an order or threats and to conduct military operations on that basis. To conduct military operations on the basis that no quarter shall be given would constitute multiple violations of the prohibition on attacking persons hors de combat (see Rule 47).
Non-international armed conflicts
Article 4 of Additional Protocol II prohibits ordering that there shall be no survivors.[11]  In his report on the establishment of the Special Court for Sierra Leone, the UN Secretary-General noted that the provisions of Article 4 had long been considered part of customary international law.[12]  Under the Statute of the International Criminal Court, “declaring that no quarter will be given” is a war crime in non-international armed conflicts.[13] 
The prohibition on ordering that there shall be no survivors is also included in military manuals which are applicable in or have been applied in non-international armed conflicts.[14]  It is an offence under the legislation of numerous States to order that no quarter shall be given in any armed conflict.[15]  Colombia’s Constitutional Court ruled that this prohibition met constitutional standards as it sought to protect human life and dignity. It also held that superior orders to cause “death outside combat” must be disobeyed.[16]  The prohibition on ordering that there shall be no survivors is also supported by official statements relating to non-international armed conflicts.[17] 
In its examination of an incident in which two wounded soldiers were killed by a member of an FMLN patrol, the UN Commission on the Truth for El Salvador found no evidence that the executions were ordered by higher levels of command or that they were carried out in accordance with an FMLN policy of killing prisoners. It reported that the FMLN acknowledged the criminal nature of the incident and tried the accused.[18] 
The ICRC has recalled the prohibition on ordering that there shall be no survivors with respect to both international and non-international armed conflicts.[19] 
Conducting hostilities on the basis that no quarter will be given would violate common Article 3 of the Geneva Conventions because it would result in the killing of persons hors de combat.[20]  It would also violate the fundamental guarantee prohibiting murder (see Rule 89).

[1] Lieber Code, Article 60 (cited in Vol. II, Ch. 15, § 7); Brussels Declaration, Article 13(d) (ibid., § 8); Oxford Manual, Article 9(b) (ibid., § 9); Hague Regulations, Article 23(d) (ibid., § 2).
[2] Report of the Commission on Responsibility (ibid., § 11).
[3] Additional Protocol I, Article 40 (adopted by consensus) (ibid., § 3).
[4] ICC Statute, Article 8(2)(b)(xii) (ibid., § 6).
[5] See, e.g., the military manuals of Argentina (ibid., § 15), Belgium (ibid., § 19), Burkina Faso (ibid., § 22), Cameroon (ibid., § 23), Colombia (ibid., § 27), Congo (ibid., § 28), France (ibid., §§ 29–30), Italy (ibid., § 34), Mali (ibid., § 36), Morocco (ibid., § 37), Nigeria (ibid., §§ 40–42), Senegal (ibid., § 44), South Africa (ibid., § 45), Switzerland (ibid., § 48), United Kingdom (ibid., §§ 50–51) and United States (ibid., § 52).
[6] See, e.g., the legislation of Armenia (ibid., § 54), Australia (ibid., § 55), Canada (ibid., § 59), China (ibid., § 60), Congo (ibid., § 61), Ethiopia (ibid., § 63), Georgia (ibid., § 64), Italy (ibid., § 67), Lithuania (ibid., § 68), Mali (ibid., § 69), Netherlands (ibid., §§ 70–71), New Zealand (ibid., § 72), Spain (ibid., § 75), United Kingdom (ibid., § 77) and United States (ibid., § 78); see also the draft legislation of Burundi (ibid., § 58) and Trinidad and Tobago (ibid., § 76).
[7] See, e.g., Canada, Military Court at Aurich, Abbaye Ardenne case (ibid., § 81); Germany, Leipzig Court, Stenger and Cruisus case (ibid., § 85); United Kingdom, Military Court at Hamburg, Peleus case (ibid., § 86), Wickman case (ibid., § 88) and Von Ruchteschell case (ibid., § 89); United Kingdom, Military Court at Brunswick, Von Falkenhorst case (ibid., § 87); United Kingdom, Court No. 5 of the Curiohaus, Hamburg-Altona, Le Paradis case (ibid., § 90); United States, Military Commission at Augsburg, Thiele case (ibid., § 91); United States, Military Tribunal at Nuremberg, Von Leeb (The High Command Trial) case (ibid., § 92).
[8] See, e.g., the military manuals of Argentina (ibid., § 16), Australia (ibid., §§ 17–18), Belgium (ibid., § 20), Benin (ibid., § 21), Cameroon (ibid., § 24), Canada (ibid., §§ 25–26), France (ibid., §§ 30 and 32), Germany (ibid., § 33), Kenya (ibid., § 35), Netherlands (ibid., § 38), New Zealand (ibid., § 39), Russian Federation (ibid., § 43), Spain (ibid., § 46), Sweden (ibid., § 47), Togo (ibid., § 49) and Yugoslavia (ibid., § 53).
[9] See, e.g., the legislation of Australia (ibid., § 56), Bosnia and Herzegovina (ibid., § 57), Croatia (ibid., § 62), Germany (ibid., § 65), Ireland (ibid., § 66), Norway (ibid., § 73), Slovenia (ibid., § 74) and Yugoslavia (ibid., § 79).
[10] See the military manuals of France (ibid., § 30) and Kenya (ibid., § 35), the statement of the United States (ibid., § 98) and the reported practice of Israel (ibid., § 95).
[11] Additional Protocol II, Article 4(1) (adopted by consensus) (ibid., § 4).
[12] UN Secretary-General, Report on the establishment of a Special Court for Sierra Leone (cited in Vol. II, Ch. 32, § 444).
[13] ICC Statute, Article 8(2)(e)(x) (cited in Vol. II, Ch. 15, § 6).
[14] See, e.g., the military manuals of Argentina (ibid., § 16), Australia (ibid., §§ 17–18), Benin (ibid., § 21), Cameroon (ibid., § 24), Canada (ibid., §§ 25–26), Colombia (ibid., § 27), France (ibid., § 32), Germany (ibid., § 33), Italy (ibid., § 34), Kenya (ibid., § 35), Netherlands (ibid., § 38), New Zealand (ibid., § 39), Nigeria (ibid., §§ 40 and 42), Russian Federation (ibid., § 43), South Africa (ibid., § 45), Spain (ibid., § 46), Togo (ibid., § 49) and Yugoslavia (ibid., § 53).
[15] See, e.g., the legislation of Australia (ibid., § 56), Bosnia and Herzegovina (ibid., § 57), Canada (ibid., § 59), Congo (ibid., § 61), Croatia (ibid., § 62), Ethiopia (ibid., § 63), Georgia (ibid., § 64), Germany (ibid., § 65), Ireland (ibid., § 66), Netherlands (ibid., § 71), New Zealand (ibid., § 72), Norway (ibid., § 73), Slovenia (ibid., § 74), United Kingdom (ibid., § 75) and Yugoslavia (ibid., § 79); see also the legislation of Italy (ibid., § 67), the application of which is not excluded in time of non-international armed conflict, and the draft legislation of Burundi (ibid., § 57) and Trinidad and Tobago (ibid., § 76).
[16] Colombia, Constitutional Court, Constitutional Case No. T-409 (ibid., § 82), Constitutional Case No. C-225/95 (ibid., § 83) and Constitutional Case No. C-578 (ibid., § 84).
[17] See, e.g., China, Announcement of the People’s Liberation Army (ibid., § 94).
[18] UN Commission on the Truth for El Salvador, Report (ibid., § 103).
[19] ICRC, Memorandum on Respect for International Humanitarian Law in Angola (ibid., § 110), Memorandum on Compliance with International Humanitarian Law by the Forces Participating in Opération Turquoise (ibid., § 111) and Communication to the Press No. 01/58 (ibid., § 113).
[20] Geneva Conventions, common Article 3 (cited in Vol. II, Ch. 32, § 1).