Related Rule
Australia
Practice Relating to Rule 108. Mercenaries
Australia’s Defence Force Manual (1994) states:
A mercenary is any person who:
a. is specially recruited locally or abroad in order to fight in an armed conflict;
b. takes part in hostilities;
c. is motivated to take part in hostilities essentially for the desire for private gain and is promised, by or on behalf of a party to the conflict, material compensation substantially in excess of that promised or paid to combatants of similar ranks and functions in the armed forces of that party;
d. is neither a national of a party to the conflict nor a resident of the territory controlled by a party to the conflict;
e. is not a member of the armed forces of a party to the conflict; and
f. has not been sent by a State which is not Party to the conflict on official duty as a member of its armed forces. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, Glossary.
Australia’s Commander’s Guide (1994) states:
A mercenary is any person who:
a) is specially recruited locally or abroad in order to fight in an armed conflict;
b) does, in fact, take a direct part in the hostilities;
c) is motivated to take part in the hostilities essentially by the desire for private gain and, in fact, is promised by or on behalf of a Party to the conflict, material compensation substantially in excess of that promised or paid to combatants of similar ranks and functions in the armed forces of that Party;
d) is neither a national of a party to the conflict nor a resident of territory controlled by a Party to the conflict;
e) is not a member of the armed forces of a Party to the conflict; and
f) has not been sent by a State which is not a Party to the conflict on official duty as a member of its armed forces. 
Australia, Law of Armed Conflict, Commanders’ Guide, Australian Defence Force Publication, Operations Series, ADFP 37 Supplement 1 – Interim Edition, 7 March 1994, Glossary, p. xxiii.
Australia’s LOAC Manual (2006) defines “mercenary” as follows:
A mercenary is any person who:
a. is specially recruited locally or abroad in order to fight in an armed conflict;
b. takes part in hostilities;
c. is motivated to take part in hostilities essentially for the desire for private gain and is promised, by or on behalf of a party to the conflict, material compensation substantially in excess of that promised or paid to combatants of similar ranks and functions in the armed forces of that party;
d. is neither a national of a party to the conflict nor a resident of the territory controlled by a party to the conflict;
e. is not a member of the armed forces of a party to the conflict; and
f. has not been sent by a state which is not party to the conflict on official duty as a member of its armed forces. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, Glossary, p. 4.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).
Australia’s Commanders’ Guide (1994) states: “Mercenaries do not have the right to be combatants or PW [prisoner of war].” 
Australia, Law of Armed Conflict, Commanders’ Guide, Australian Defence Force Publication, Operations Series, ADFP 37 Supplement 1 – Interim Edition, 7 March 1994, § 708.
Australia’s LOAC Manual (2006) states:
Mercenaries are not entitled to be PW [prisoners of war], although their captors may afford them the protection of such status. Even if not treated as PW, captured mercenaries remain entitled to fundamental guarantees provided by G. P. I. [1977 Additional Protocol I]. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, § 10.6.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).
At the CDDH, Australia stated that it held the view that “mercenaries, who are in the hands of a Party to an armed conflict to which draft Protocol I applies, are entitled to the benefits of the treatment provided for by Article 65 [now Article 75] of that Protocol”. 
Australia, Statement at the CDDH, Official Records, Vol. VI, CDDH/SR.41, 26 May 1977, p. 175; see also p. 176.