Соответствующая норма
Kenya
Practice Relating to Rule 145. Reprisals
Section C. Proportionality of reprisals
Kenya’s LOAC Manual (1997) states: “Under customary law, reprisals are permitted to counter unlawful acts of warfare. They can only be taken if: … they are proportionate to the breach of the law of war committed by the enemy.” 
Kenya, Law of Armed Conflict, Military Basic Course (ORS), 4 Précis, The School of Military Police, 1997, Précis No. 4, p. 4.