Related Rule
Sweden
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 3.2.1.5, 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.
In 2009, in answer to a written question in Parliament regarding international law and the Israeli-Palestinian conflict, Sweden’s Minister for Foreign Affairs stated:
All parties to an armed conflict shall respect international humanitarian law. Sweden has expressed, both bilaterally and through multilateral forums, that international humanitarian law and, especially, the protection of civilians must be respected by both parties to the conflict in and around Gaza.
Sweden has also been forced to conclude that Israel and Hamas have violated their respective obligations. Both sides have violated their obligation to distinguish between military targets and the civilian population. 
Sweden, Answer by the Minister for Foreign Affairs to written question 2008/09:470 in Parliament regarding international law and the Israeli-Palestinian conflict, 23 January 2009.
In 2009, in answer to a written question in Parliament regarding the EU and massive ordnance penetrator bombs, Sweden’s Minister for Foreign Affairs stated:
International humanitarian law or the laws of war contain rules that aim to alleviate the effects of war. One of the most important principles is the principle of distinction, which entails the duty to distinguish between military targets and civilians[.] 
Sweden, Answer by the Minister for Foreign Affairs to written question 2009/10:114 in Parliament regarding the EU and massive ordnance penetrator bombs, 28 October 2009.