HUMANITARIAN AND SECURITY LAW
JUS IN BELLO – MEANS AND METHODS OF WARFARE
7. JUS IN BELLO- MEANS AND METHODS OF WARFARE
7.1. MEANS & METHODS OF WARFARE
7.1.1. MEANS OF WARFARE: LIMITATIONS ON UNNECESSARY SUFFERING, PROHIBITED
WEAPONS
► A return to Hague Law in this area of IHL
o Recall: ‘Geneva Law’ focusses on reconciling military necessity and principles of humanity (cf.
Geneva Conventions)
o ‘Hague Law’ (based in the Hague Regulations) more technical, regulating rules on military
operations and how hostilities are conducted:
▪ Three key areas:
• Superfluous injury/unnecessary suffering,
• explicitly prohibited weapons,
• Potentially prohibited weapons (e.g. nuclear weapons).
▪ Rules which complement the Geneva Conventions.
SUPERFLUOUS INJURY/UNNECESSARY SUFFERING
► Long-standing principle, codified in Art 35(2) AP I: a prohibition on weapons/means/methods that
cause ‘superfluous injury and unnecessary suffering’:
o 35(2) AP I is a self-standing condition, not a reflection of prohibited weapons => it applies to
all weapons.
► It’s about how you target them
► Nuclear Weapons, ICJ 1996: ‘cardinal principle’ of IHL
► ‘Unnecessary suffering’=either no military necessity (other means of achieving the objective) or
suffering is ‘clearly excessive’ vis-a-vis the objective sought
o Suffering which could have been avoided.
o Embedded a condition of proportionality.
o Not only a question of methods, but also of operations (e.g., wrong targeting) => broader than
specific treaties prohibiting weapons.
1
, HUMANITARIAN AND SECURITY LAW
JUS IN BELLO – MEANS AND METHODS OF WARFARE
► How does one determine what is ‘superfluous or unnecessary’? Balancing test and proportionality
analysis?
o Decisive factors:
▪ Availability of alternative means and methods (‘only means available’)
▪ The degree of suffering caused (but how to quantify?)
o Underpinned by core principles of military necessity and CA 3/Martens clause ‘principle of
humanity’
o If in balance, a party may only to use the minimum force required to achieve the ‘legitimate
purpose’ of armed conflict: the defeat of the adversary as easily, quickly and with the
‘minimum expenditure’ of life and resources.
► What factors to account for in practice?
o ICRC: does a weapon/means ‘render death inevitable’ (is it lethal?) or result in permanent
disability?
▪ The more inevitable the death, the more precautions need to be taken.
o Doctrinal Debate: Can AP I 35(2) be enough, or do you also need treaty practice prohibiting
certain weapons? => Not entirely clear.
▪ 1925 Geneva Gas Protocols, 1980 Convention on Excessively Injurious Conventional
Weapons, 1997 Ottawa Convention on Landmines – all of these prohibit certain
weapons => so what happens when you do not have an explicit prohibition => is Art.
35(2) sufficient => generally need to be cautious in fulfilling the criteria of Art. 35(2).
▪ Rome Statute art 8(2)(b)(xx) lists both the test and a condition that the means
employed is subject to a prohibition and listed in an annex—but the annex does not yet
exist! But see articles 8(2)(b)xvii—xix, where no annex is needed: poisonous
gases/weapons, asphyxiating gases/weapons (and analogous), exploding, expanding or
flattening (‘dum dum’) bullets
o AP I art 35(2) as framework
▪ Starting point + customary prohibitions might evolve through practice.
o AP I art 36: obligation of conduct to state and private entities within states => new weaponry
must be assessed against the test, ICRC maintains information on domestic procedures and
reviews, even though these are not binding.
2
, HUMANITARIAN AND SECURITY LAW
JUS IN BELLO – MEANS AND METHODS OF WARFARE
EXPLICITLY PROHIBITED WEAPONS:
► Since 1907 Hague Conventions, long-standing treaty practice in this respect1:
o Poison/poisonous weapons: HC IV (Hague Regulations)
o Exploding bullets (1868 St Petersburg D)
o Expanding/flattening bullets (1899 Hague Declaration IV
o 1972 Biological Weapons Convention (BWC)
o 1993 Chemical Weapons Convention (CWC, also creating the OPCW in The Hague)
o 1980 Conventional Weapons causing Excessive Injuries (CCW)
o 1997 Ottawa Anti-Personnel Landmines Convention
o 2008 Cluster Munitions Convention (but not US/Israel)
► Nuclear Weapons Special Case
o 1967 Nuclear Non-Proliferation Treaty (NPT): disarmament, arms control, but not prohibition
▪ 2 tier system – Nuclear Weapon states would not help non-nuclear weapons states
with nuclear technology and non-nuclear weapons states would seize their own
research efforts => logic of disarmament.
o AP I: many States expressly excluded nuclear weapons from its scope (not only nuclear powers)
o ICJ, Nuclear Weapons: Nuclear Weapons are subject to IHL rules on necessity and
proportionality, and distinction— but not unlawful per se (casting vote!)
o 2021 Treaty on the Prohibition of Nuclear Weapons: but not ratified by any nuclear weapons-
holding State and many of their allies (including the five permanent members of UNSC and no
NATO state).
o Unlikely for a rule of customary rule to exist, since all the specially affected states are reluctant
to sign and ratify.
o TPN1→ exclusively non-nuclear states have signed, Sweden is the only one from NATO that
signed (the rest of the NATO is under the nuclear umbrella of the nuclear states)
o Factually violate all IHl laws
POTENTIALLY UNLAWFUL WEAPONS
► Overarching notion: prohibition of ‘indiscriminate attacks’ (AP I, art 51(4)), those which are not aimed
at a military objective, or cannot be limited or controlled, and can strike military and civilian objects
without distinction.
1
Check UN Treaty Collection for Ratifications - treaties.un.org/Pages/AdvanceSearch.aspx?tab=UNTS&clang=_en
3
JUS IN BELLO – MEANS AND METHODS OF WARFARE
7. JUS IN BELLO- MEANS AND METHODS OF WARFARE
7.1. MEANS & METHODS OF WARFARE
7.1.1. MEANS OF WARFARE: LIMITATIONS ON UNNECESSARY SUFFERING, PROHIBITED
WEAPONS
► A return to Hague Law in this area of IHL
o Recall: ‘Geneva Law’ focusses on reconciling military necessity and principles of humanity (cf.
Geneva Conventions)
o ‘Hague Law’ (based in the Hague Regulations) more technical, regulating rules on military
operations and how hostilities are conducted:
▪ Three key areas:
• Superfluous injury/unnecessary suffering,
• explicitly prohibited weapons,
• Potentially prohibited weapons (e.g. nuclear weapons).
▪ Rules which complement the Geneva Conventions.
SUPERFLUOUS INJURY/UNNECESSARY SUFFERING
► Long-standing principle, codified in Art 35(2) AP I: a prohibition on weapons/means/methods that
cause ‘superfluous injury and unnecessary suffering’:
o 35(2) AP I is a self-standing condition, not a reflection of prohibited weapons => it applies to
all weapons.
► It’s about how you target them
► Nuclear Weapons, ICJ 1996: ‘cardinal principle’ of IHL
► ‘Unnecessary suffering’=either no military necessity (other means of achieving the objective) or
suffering is ‘clearly excessive’ vis-a-vis the objective sought
o Suffering which could have been avoided.
o Embedded a condition of proportionality.
o Not only a question of methods, but also of operations (e.g., wrong targeting) => broader than
specific treaties prohibiting weapons.
1
, HUMANITARIAN AND SECURITY LAW
JUS IN BELLO – MEANS AND METHODS OF WARFARE
► How does one determine what is ‘superfluous or unnecessary’? Balancing test and proportionality
analysis?
o Decisive factors:
▪ Availability of alternative means and methods (‘only means available’)
▪ The degree of suffering caused (but how to quantify?)
o Underpinned by core principles of military necessity and CA 3/Martens clause ‘principle of
humanity’
o If in balance, a party may only to use the minimum force required to achieve the ‘legitimate
purpose’ of armed conflict: the defeat of the adversary as easily, quickly and with the
‘minimum expenditure’ of life and resources.
► What factors to account for in practice?
o ICRC: does a weapon/means ‘render death inevitable’ (is it lethal?) or result in permanent
disability?
▪ The more inevitable the death, the more precautions need to be taken.
o Doctrinal Debate: Can AP I 35(2) be enough, or do you also need treaty practice prohibiting
certain weapons? => Not entirely clear.
▪ 1925 Geneva Gas Protocols, 1980 Convention on Excessively Injurious Conventional
Weapons, 1997 Ottawa Convention on Landmines – all of these prohibit certain
weapons => so what happens when you do not have an explicit prohibition => is Art.
35(2) sufficient => generally need to be cautious in fulfilling the criteria of Art. 35(2).
▪ Rome Statute art 8(2)(b)(xx) lists both the test and a condition that the means
employed is subject to a prohibition and listed in an annex—but the annex does not yet
exist! But see articles 8(2)(b)xvii—xix, where no annex is needed: poisonous
gases/weapons, asphyxiating gases/weapons (and analogous), exploding, expanding or
flattening (‘dum dum’) bullets
o AP I art 35(2) as framework
▪ Starting point + customary prohibitions might evolve through practice.
o AP I art 36: obligation of conduct to state and private entities within states => new weaponry
must be assessed against the test, ICRC maintains information on domestic procedures and
reviews, even though these are not binding.
2
, HUMANITARIAN AND SECURITY LAW
JUS IN BELLO – MEANS AND METHODS OF WARFARE
EXPLICITLY PROHIBITED WEAPONS:
► Since 1907 Hague Conventions, long-standing treaty practice in this respect1:
o Poison/poisonous weapons: HC IV (Hague Regulations)
o Exploding bullets (1868 St Petersburg D)
o Expanding/flattening bullets (1899 Hague Declaration IV
o 1972 Biological Weapons Convention (BWC)
o 1993 Chemical Weapons Convention (CWC, also creating the OPCW in The Hague)
o 1980 Conventional Weapons causing Excessive Injuries (CCW)
o 1997 Ottawa Anti-Personnel Landmines Convention
o 2008 Cluster Munitions Convention (but not US/Israel)
► Nuclear Weapons Special Case
o 1967 Nuclear Non-Proliferation Treaty (NPT): disarmament, arms control, but not prohibition
▪ 2 tier system – Nuclear Weapon states would not help non-nuclear weapons states
with nuclear technology and non-nuclear weapons states would seize their own
research efforts => logic of disarmament.
o AP I: many States expressly excluded nuclear weapons from its scope (not only nuclear powers)
o ICJ, Nuclear Weapons: Nuclear Weapons are subject to IHL rules on necessity and
proportionality, and distinction— but not unlawful per se (casting vote!)
o 2021 Treaty on the Prohibition of Nuclear Weapons: but not ratified by any nuclear weapons-
holding State and many of their allies (including the five permanent members of UNSC and no
NATO state).
o Unlikely for a rule of customary rule to exist, since all the specially affected states are reluctant
to sign and ratify.
o TPN1→ exclusively non-nuclear states have signed, Sweden is the only one from NATO that
signed (the rest of the NATO is under the nuclear umbrella of the nuclear states)
o Factually violate all IHl laws
POTENTIALLY UNLAWFUL WEAPONS
► Overarching notion: prohibition of ‘indiscriminate attacks’ (AP I, art 51(4)), those which are not aimed
at a military objective, or cannot be limited or controlled, and can strike military and civilian objects
without distinction.
1
Check UN Treaty Collection for Ratifications - treaties.un.org/Pages/AdvanceSearch.aspx?tab=UNTS&clang=_en
3
