القاعدة ذات الصلة
Spain
Practice Relating to Rule 106. Conditions for Prisoner-of-War Status
Section C. Situations where combatants cannot distinguish themselves
Spain’s LOAC Manual (1996) states that guerrilleros are considered lawful combatants if “they operate in occupied territory, carry arms openly during each engagement and during any movement towards the place from which or towards which an attack is to be launched”. 
Spain, Orientaciones. El Derecho de los Conflictos Armados, Publicación OR7-004, 2 Tomos, aprobado por el Estado Mayor del Ejército, Division de Operaciones, 18 March 1996, Vol. I, § 1.3.a.(1).
Spain’s LOAC Manual (2007) states that “guerrillas are only considered lawful combatants when they act in occupied territory and carry their arms openly during operations and any movement towards a place from or on which an attack is to be launched”. 
Spain, Orientaciones. El Derecho de los Conflictos Armados, Tomo 1, Publicación OR7–004, (Edición Segunda), Mando de Adiestramiento y Doctrina, Dirección de Doctrina, Orgánica y Materiales, 2 November 2007, § 1.3.a.(1).
The manual further states: “It is accepted that, in some cases, combatants are unable to distinguish themselves as such because of the ‘nature of the hostilities’.” 
Spain, Orientaciones. El Derecho de los Conflictos Armados, Tomo 1, Publicación OR7–004, (Edición Segunda), Mando de Adiestramiento y Doctrina, Dirección de Doctrina, Orgánica y Materiales, 2 November 2007, § 2.4.c.(8).
At the CDDH, Spain abstained in the vote on draft Article 42 of the Additional Protocol I (now Article 44) because:
The text presented does not guarantee the safety of the civilian population, which is the essential aim of the instruments under consideration. In the view of this delegation, the terms in which the article is drafted could favour the development of the new phenomenon known as urban guerrilla warfare and, therefore, a certain form of terrorism, thus constituting a grave danger to the security of States and a step on the road to international subversion. 
Spain, Statement at the CDDH, Official Records, Vol. VI, CDDH/SR.55, 26 May 1977, p. 138.
Upon ratification of the 1977 Additional Protocol I, Spain stated:
It is understood that the criteria mentioned in sub-paragraph b of Article 44(3) on the distinction between combatants and civilians can be applied only in occupied territories. The Spanish Government also interprets the expression “military deployment” to mean any movement towards a place from which or against which an attack is going to be launched. 
Spain, Interpretative declarations made upon ratification of the 1977 Additional Protocol I, 21 April 1989, § 4.