Соответствующая норма
Practice Relating to Rule 1. The Principle of Distinction between Civilians and Combatants
Section A. The principle of distinction
Sweden’s IHL Manual (1991) states: “A distinction shall always be made between persons participating in hostilities and who are thereby legitimate objectives, and members of the civilian population, who may not constitute objectives in warfare.” 
Sweden, International Humanitarian Law in Armed Conflict, with reference to the Swedish Total Defence System, Swedish Ministry of Defence, January 1991, Section, p. 40.
The manual considers that the principle of distinction as stated in Article 48 of the 1977 Additional Protocol I is part of customary international law. 
Sweden, International Humanitarian Law in Armed Conflict, with reference to the Swedish Total Defence System, Swedish Ministry of Defence, January 1991, Section 2.2.3, p. 19.
In 2007, in an answer to a question in Parliament, the Swedish Minister of Trade stated:
Then we have the humanitarian law principles regarding distinction, proportionality and unnecessary suffering, to which particular attention should be given. This means that a distinction must be drawn between military targets on the one hand and the civilian population and its property on the other, and that attacks may only be targeted at military targets. 
Sweden, Answer by the Minister of Trade to a Parliamentary interpellation on the sale of cluster munitions to the United States, 13 November 2007, Parliamentary Protocol 2007/08:23, § 18, Anf. 124.
Humanitarian law is based on a number of fundamental principles. They are apparent in current treaties and customary law and express the core of humanitarian law. They concern the principles of distinction, proportionality and precaution, the prohibition on causing superfluous damage and unnecessary suffering and the principle of non-discrimination as well as the so called Martens Clause. 
Sweden, Government Bill 2013/14:146 on criminal liability for genocide, crimes against humanity and war crimes, 20 February 2014, p. 33.
The annual report of the Secretary-General paints a gloomy picture of the situation around the world for children in armed conflict. ISIL has been listed as violating all triggers of violence against children, a result of their appalling atrocities. In Syria, the systematic use of indiscriminate aerial weapons, such as barrel bombs, account for the overwhelming majority of civilian casualties, including children. This cannot be allowed to continue. And during hostilities in Gaza last summer, civilians, including children, bore the brunt of the suffering. At least 540 Palestinian children were killed … The scale of the impact on children was unprecedented and unacceptable.
These facts … are utterly disturbing and raise serious concern about the observance of the rules of international humanitarian law, including the [principle] of distinction … and respect for international human rights law. 
Sweden, Statement by the permanent representative of Sweden at the UN Security Council Open Debate on Children and Armed Conflict made on behalf of Finland, Iceland, Norway and Sweden, 18 June 2015.