Practice Relating to Rule 10. Civilian Objects’ Loss of Protection from Attack
Section B. Situations of doubt as to the character of an object
Israel’s Manual on the Laws of War (1998) states: “In cases where there is doubt as to whether a civilian object has turned into a military objective, the  Additional Protocols state that one is to assume that it is not a military objective unless proven otherwise.”
Israel’s Manual on the Rules of Warfare (2006) states:
In the case of incidents in which there is a doubt as to whether the target changed its status from civilian to military, the Additional Protocols determine that it should be assumed that it is not a military target unless proven otherwise.
The Manual on the Rules of Warfare (2006) is a second edition of the Manual on the Laws of War (1998).
The Report on the Practice of Israel states:
In principle, in cases of significant doubt as to whether a target is legitimate or civilian, the decision would be to refrain from attacking the target. It should be stressed that the introduction of the adjective “significant” in this context is aimed at excluding those cases in which there exists a slight possibility that the definition of the target as legitimate is mistaken. In such cases, the decision whether or not to attack rests with the commander in the field, who has to decide whether or not the possibility of mistake is significant enough to warrant not launching the attack.
In 2009, in a report on Israeli operations in Gaza between 27 December 2008 and 18 January 2009 (the “Gaza Operation”, also known as “Operation Cast Lead”), Israel’s Ministry of Foreign Affairs stated:
A dual use objective may be attacked if reliable, conclusive and up-to-date information confirms that it serves the military activities of the enemy, and subject to the principle of proportionality. In case of doubt, such objective shall be presumed to be civilian.