Related Rule
Practice Relating to Rule 7. The Principle of Distinction between Civilian Objects and Military Objectives
Section C. Attacks against civilian objects in general
Australia’s Defence Force Manual (1994) provides:
Non-combatants and civilian objects are protected from attack, that is, they are not legitimate objects of attack. The law of armed conflict therefore requires that belligerents maintain the clear distinction between armed forces and civilians taking no direct part in hostilities; that is, between combatants and non-combatants, and between objects that might legitimately be attacked and those protected from attack. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 210; see also § 503(b) and 531.
Australia’s LOAC Manual (2006) states:
2.11 … Non-combatants and civilian objects are protected from attack, that is, they are not legitimate objects of attack …
9.17 Military operations may only be directed against military objectives and not against the civilian population and civilian objects. …
9.18 It follows from the general rule that it is forbidden to attack the civilian population, individual civilians and civilian objects as a deliberate method of warfare. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, §§ 2.11 and 9.17–9.18; see also §§ 5.3 and 5.35.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).
Australia’s Criminal Code Act (1995), as amended to 2007, states with respect to serious war crimes that are committed in the course of an international armed conflict:
268.36 War crime – attacking civilian objects
A person (the perpetrator) commits an offence if:
(a) the perpetrator directs an attack; and
(b) the object of the attack is not a military objective; and
(c) the perpetrator’s conduct takes place in the context of, and is associated with, an international armed conflict.
Penalty: Imprisonment for 15 years. 
Australia, Criminal Code Act, 1995, as amended to 2007, Chapter 8, § 268.36, p. 326.
Australia’s ICC (Consequential Amendments) Act (2002) incorporates in the Criminal Code the war crimes defined in the 1998 ICC Statute, including “attacking civilian objects” in international armed conflicts. 
Australia, ICC (Consequential Amendments) Act, 2002, Schedule 1, § 268.36.