Règle correspondante
Practice Relating to Rule 145. Reprisals
Section C. Proportionality of reprisals
The Military Manual (1993) of the Netherlands, referring to customary law, states that reprisals are in principle allowed, provided that a number of conditions are fulfilled. Among these conditions, it states: “The damage to be caused to the adversary and the damage unlawfully suffered must be proportional.” 
Netherlands, Toepassing Humanitair Oorlogsrecht, Voorschift No. 27-412/1, Koninklijke Landmacht, Ministerie van Defensie, 1993, p. IV-5.
The Military Manual (2005) of the Netherlands states:
On the basis of customary law, it used to be assumed that reprisals were allowed in principle by the law of war, provided that a number of conditions were met:
- there must be proportionality between the damage to be done and the damage found to be unjust. 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 0423.
In its judgment in the Rauter case in 1948, the Special Court (War Criminals) at The Hague referred to the judgment of the US Military Tribunal at Nuremberg in the List case (The Hostages Trial), as well as to the conditions required for reprisals in general by the UK and US military regulations and stated that, accordingly, the taking of reprisals required a due proportion between the acts undertaken in reprisals and the original offence. It found, inter alia, that by killing several hostages at a time for the death of one member of the German authorities, the accused had committed excessive reprisals in violation of the rule requiring due proportion. 
Netherlands, Special Court (War Criminals) at The Hague, Rauter case, Judgment, 4 May 1948.
In its judgment on appeal in 1949, the Special Court of Cassation of the Netherlands also stated, inter alia, that genuine reprisals may be taken, “provided they are taken within certain limits and provided attention is paid to a certain proportion”. 
Netherlands, Special Court of Cassation, Rauter case, Judgment, 12 January 1949.
In an explanatory memorandum submitted to the Dutch Parliament in the context of the ratification procedure of the Additional Protocols, the Government of the Netherlands stated that for the reprisal to be lawful, “the violation of the law caused by the reprisal must be proportionate with the violation(s) committed by the adverse party”. 
Netherlands, Lower House of Parliament, Explanatory memorandum for the ratification of the Additional Protocols, 1983–1984 Session, Doc. 18 277 (R 1247), No. 3, pp. 40.
In its written statement submitted to the ICJ in the Nuclear Weapons case in 1995, the Netherlands stated:
The Netherlands Government … believes that even if it were to be assumed that the (first) use of nuclear weapons by a State were unlawful per se under present international law – quod non -, this would not necessarily exclude the permissibility of the use of nuclear weapons by way of belligerent reprisal against an unlawful use of (nuclear) weapons, provided of course the retaliating State observed the conditions set by international law for the taking of lawful reprisals, i.e. satisfies, inter alia, the requirement that the retaliation is proportionate and serves as an ultimum remedium. 
Netherlands, Written statement submitted to the ICJ, Nuclear Weapons case, 16 June 1995, § 29.
[emphasis in original]