Related Rule
Australia
Practice Relating to Rule 30. Persons and Objects Displaying the Distinctive Emblem
Australia’s Defence Force Manual (1994) provides that “firing upon … the Red Cross symbol” constitutes a grave breach or a serious war crime likely to warrant institution of criminal proceedings. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 1315(q); see also Law of Armed Conflict, Commanders’ Guide, Australian Defence Force Publication, Operations Series, ADFP 37 Supplement 1 – Interim Edition, 7 March 1994, § 1305(q).
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:
268.66 War crimeattacking persons or objects using the distinctive emblems of the Geneva Conventions
(1) A person (the perpetrator) commits an offence if:
(a) the perpetrator attacks one or more persons; and
(b) the person or persons are using, in conformity with the Geneva Conventions or the Protocols to the Geneva Conventions, any of the distinctive emblems of the Geneva Conventions; and
(c) the perpetrator intends the persons so using such an emblem to be the object of the attack; and
(d) the perpetrator’s conduct takes place in the context of, and is associated with, an international armed conflict.
Penalty: Imprisonment for life.
(3) Strict liability applies to paragraphs (1)(b). 
Australia, Criminal Code Act, 1995, as amended to 2007, Chapter 8, § 268.66, pp. 344–345.
The Criminal Code Act also states, with respect to crimes that are serious violations of the laws and customs of war applicable in a non-international armed conflict:
268.78 War crimeattacking persons or objects using the distinctive emblems of the Geneva Conventions
(1) A person (the perpetrator) commits an offence if:
(a) the perpetrator attacks one or more persons; and
(b) the person or persons are using, in conformity with the Geneva Conventions or the Protocols to the Geneva Conventions, any of the distinctive emblems of the Geneva Conventions; and
(c) the perpetrator intends the persons so using such an emblem to be the object of the attack; and
(d) the perpetrator’s conduct takes place in the context of, and is associated with, an armed conflict that is not an international armed conflict.
Penalty: Imprisonment for life.
(3) Strict liability applies to paragraphs (1)(b). 
Australia, Criminal Code Act, 1995, as amended to 2007, Chapter 8, § 268.78, pp. 354–355.
Australia’s ICC (Consequential Amendments) Act (2002) incorporates in the Criminal Code the war crimes defined in the 1998 ICC Statute, including “attacking persons or objects using the distinctive emblems of the Geneva Conventions” in both international and non-international armed conflicts. 
Australia, ICC (Consequential Amendments) Act, 2002, Schedule 1, §§ 268.66 and 268.78.