Sources of International Law

• Author: John H. Currie
• Pages: 80-122

Chapter 3

SOURCES OF

INTERNATIONAL LAW

a. relevaNCe of “sourCes”

The domestic lawyer or law student is rarely preoccupied with the

sources of domestic law and even more rarely w ith its binding author-

ity. Most domestic legal systems are suff‌iciently mature that the sources

of the law are well established and grounded in an authoritative, al-

beit frequently complex, constitutional and institutional framework. In

Canada, for example, it is a virtual article of faith that all binding legal

rules f‌ind their source either in the enactments of constitutionally-

sanctioned legislative bodies (Parliament and provincial legislatures)

or their delegates (for example, federal or provincial cabinets and mu-

nicipal authorities), or in the common law developed by the courts. In

other words, in most domestic legal orders, it is a given that constitu-

tionally competent institutions are assigned the task of promulgating

and enforcing the law.

The situation is entirely different in the international legal system.

As we have seen,1that system is typif‌ied by the absence of a formal

constitutional structure, a lack of central organization, and only a

tenuous institutional framework in which states participate on a purely

voluntary basis. Hence, there is no central or constitutionally author-

ized legislature or law-making authority in international law. While

1 See Chapter 1.

80

Sources of Inter national Law81

the Charterof the United Nations2 may have the outward appearance of

an international constitution, it is at its root simply an international

treaty, binding upon states who are parties to it in accordance with

international treaty law.3 Further, while the UN enjoys near-universal

participation by the world’s states4 and certainly plays an important

institutional role in providing a permanent forum for sustained inter-

national dialogue and diplomacy, it has no formal law-making powers

of its own.5 The powers of the UN General Assembly, for example, are

limited to discussing and making recommendations on questions or

matters coming within the scope of the UN Charter.6 The International

Court of Justice (ICJ), being the “principal judicial organ of the United

Nations,”7 only has jurisdiction to give advisory opinions to various

UN organs and agencies and to decide cases submitted to it with the

consent of the parties.8 In any event, it has no power to create binding

precedent as does a common law court.9Even the UN Security Council,

which is given the power to make determinations and impose binding

measures in matters of international peace and security, only has the

authority to bind member states of the organization, that is, parties to

the UN Charter.10 In that sense, the Security Council is simply exercis-

2 Charter of the United Nat ions, 26 June 1945, Can. T.S. 1945 No. 7 (entered into

force 24 October 1945) [UN Charter].

3 See Chapter 4.

4 At the time of wr iting 192 states were members of the Un ited Nations.

5 But see O. Schachter, “United Nat ions Law” (1994) 88 A.J.I.L. 1. It is of course

true that , in “providing a perma nent forum for sustained inter national dialogue

and diplomacy,” the UN has multipl ied the law-creating oppor tunities available

to states, and i n that sense fosters the g rowth of international l aw. The point

made here, however, is th at the UN and its organs are not form al sources of

internat ional law in their own ri ght.

6 See, generally, UN Char ter, above note 2, Chapter IV. Note, however, that the

General As sembly has the power to control the bud get of the UN (Article 17);

to elect members to va rious UN bodies such as t he Security Council (Art icle

23(1)), the Economic and Social Counc il (Article 61), the Trusteeship C ouncil

(Article 86(1)(c)), and the International Cour t of Justice (Statute of the Inter-

national Court of Ju stice,belownote 8, Article 4); and to admit, sus pend, or

expel membe rs to or from the UN (Articles 4 –6). It also enjoys cer tain other

powers in resp ect of the administrat ion of trust territorie s (Chapters XII–X III).

7 UN Charter, abovenote 2, Art icle 92.

8 Ibid., Article 96; Sta tute of the International Cou rt of Justice, 26 June 1945, Can.

T.S. 1945 No. 7 (entered into force 24 October 1945), Article 36 [ICJ Statute].

9 Case Concerning East Tim or (Portugal v. Australia) [1995] I.C.J. Rep. 90 at 101,

para. 26; ICJ Statute, ibid., Ar ticle 59.

10Note, however, that t he UN Charter provides th at the United Nations shall en-

sure that non-memb ers comply with the principle s of the organization insof ar

as necessa ry to maintain int ernational peace and s ecurity: UN Charter, above

PUBLIC INTERNATIONA L LAW82

ing enforcement authority delegated to it by states in a treaty.11 Fur ther,

in exercising these powers it is acting as a political or executive organ

rather than as a judicial or law-making institution promulgating law

with general normative effect.12

This perhaps remarkable fact — that there is no central law-mak-

ing authority in our international legal system — is, in reality, hardly

surprising at all. It is a natural result of the underlying structure of

the international “community,” which comprises, as we have seen, a

note 2, Article 2(6). On the debate thi s provision has generated in l ight of the

general rule of t reaty law that treat ies do not create obligations for non-part ies,

see Chapter 4, Sect ion G(4).

11See, in p articular, Article s 25, 39–42, 48–49, and 103 of the UN Char ter, ibid.,

which together const itute the core of the Securit y Council’s binding and over-

riding author ity to require states to t ake certain steps to ma intain or restore

internat ional peace and securit y.

12See Case Concer ning Armed Activities on the Territor y of the Congo (Democratic

Republic of the Congo v. Uganda), Provisional Measures, O rder of 1 July 2000,

[2000] I.C.J. Rep. 111 at para. 36; Case Concerning Military and Paramilitary

Activities in and again st Nicaragua (Nicaragua v. United States of America)

Jurisdiction an d Admissibility, Judgment, [1984] I.C.J. Rep. 392 at para. 95; Case

Concerning Applicat ion of the Convention on the Prevention a nd Punishment of

the Crime of Genocid e (Bosnia and Herzegovina v. Yugoslavia (Serbia and Monte-

negro)), Provisional Measures, Orde r of 8 April 1993, [1993] I.C.J. Rep. 3 at para.

33; Case Concerning Questio ns of Interpretation and Ap plication of the 1971

Montreal Convention Ar ising from the Aerial Incident a t Lockerbie (Libyan Arab Ja-

mahiriya v. United Kingdom), Provisional Measures, Order of 14 April 1992, [1992]

I.C.J Rep. 114 at para. 40. But note that the Secur ity Council has, on occa sion,

exercised it s power to establish free-st anding judicial in stitutions, such as the

Internation al Criminal Tribun al for the Former Yugoslavia and the Inte rnation-

al Crimi nal Tribunal for Rwanda. On the Trib unal for the Former Yugoslavia,

see Report of th e Secretary General Pursuant to Paragraph 2 of Secur ity Council

Resolution 808 (1993), UN SCOR, 48th Year, UN Doc. S/25704, S/25704/Add.1, S/

25704/Corr.1; SC Res. 827 (25 May 1993), UN SCOR, 48th Year, UN Doc. S/R ES/

827(1993); Statute of the Internati onal Tribunal, adopte d by SC Res. 827, ibid.,

Annex, UN Doc. 2 5704 (1993), as amended by SC Re s. 1166 (13 May 1998), UN

SCOR, 53rd Year, UN Doc. S/RE S/1166(1998); as amended by SC Res. 1329 (30

November 2000), UN SCOR, 55th Year, UN Doc. S/R ES/1329(2000). See also

Prosecutor v. Tadic(1995), 35 I.L.M. 32 at paras. 28–35 (ICTY Appea ls Cham-

ber). On the Tribunal for Rwanda, s ee SC Res. 955 (8 November 1994), UN

SCOR, 49th Year, UN Doc. S/ RES/955(1994); Statute of the Inter national Tribunal

for Rwanda, adopted by SC Re s. 955 (1994), UN SCOR, 49th Year, UN Doc.

S/INF/50 (1994). It should also be noted that t he Security Council ha s recently

begun adopti ng binding resolutions requi ring states to take leg islative steps

within t heir domestic legal systems t o address, for example, issue s of terrorist

f‌inancing a nd proliferation of weapons of mas s destruction: see, for exa mple,

UNSC Resolution 1373, 28 Septem ber, 2001, UN Doc. S/R ES/1373 (2001);

UNSC Resolution 154 0, 28 April, 2004, UN Doc. S/R ES/1540 (2004).