Rules of evidence before the international court of justice
Generally, the rules of evidence in international law comprise rules which have usually either been accepted as parties, which vary from case-to-case or, if such explicit agreements are absent, the rules which “have been adopted and applied in practice by international tribunals". 
The International Court of Justice  has the competence to establish the existence of a fact, which, if ascertained and proved, will constitute a breach of an international obligation.  The judges in the Nicaragua case, said, defining the scope of the decisions of the Court, that “in dealing with questions of evidence, the Court proceeds upon the basis that its decision will be based upon the facts occurring up to the close of the oral proceedings on the merits of the case."  Additionally, it was declared that the Court is bound to confine its decision to the points of law which are absolutely essential to the settlement of the disputes before it.  To enable the court to give an informed decision, Article 48 of the Statute of the International Court of Justice  provides that the Court shall “make all arrangements connected with the taking of evidence".  A host of other general provisions, in both the Statute and the Rules of the Court  enable the Court to admit and evaluate evidence with a freedom unknown to courts in domestic jurisdictions, but it is pertinent to note that these documents deal with evidence in only superficial terms. Consequently, it has been left to the Court itself to determine the procedure for evidence based on the unique facts of each case, and various decisions of the Court have established principles governing the burden and standard of proof, admissibility of evidence, etc.
This paper shall begin with the decision of the Court in the Corfu Channel Case,  which laid the groundwork for circumstantial and secret evidence-related procedure. The scope of the paper shall be limited to a discussion of the rules of evidence that govern the International Court of Justice, as Corfu Channel was a decision of this Court. The evolution of these rules shall be outlined through an analysis of precedents, which interpret the general provisions in the Statute and Rules in a variety of remarkable ways. To render an extensive analysis possible, and due to the constraint on the number of words, the arguments regarding only admissibility, burden of proof and standard of proof are addressed.
THE EVIDENTIARY RULES LAID DOWN IN THE CORFU CHANNEL DECISION
This case was the Court’s first contentious case. The United Kingdom brought the case against Albania, claiming that Albania was responsible for the mines present in the Corfu Channel, which was a strait between Albania and Greece. As British warships passed through the Channel in October, 1946, two ships struck mines and were damaged.  To prove that Albania was aware of the presence of mines, indirect evidence was relied upon. It was concluded by the Court that Albania kept a close watch on its waters and could observe mine-laying from the coast. Therefore, there was a violation of international law by Albania as it failed to warn the United Kingdom. The contention of Albania that the United Kingdom had violated Albanian sovereignty by sending warships through the Channel was dismissed, and the United Kingdom was allowed to deny the production of certain reports on the ground of secrecy. Other direct evidence produced by the United Kingdom, the Court said, contradicted Albania’s claim, and the United Kingdom could not be held to have violated international law.
It is apparent that a standard of proof lower than necessary was applied in favour of the United Kingdom when the Court permitted a “liberal recourse to inferences of fact". Yet, this differential standard may be considered sound because the United Kingdom did not have the opportunity to obtain direct evidence legally, while Albania had the ability to gather evidence regarding the passage of British ships through the Channel.  Therefore, it may be concluded that liberal reliance on circumstantial evidence is deemed acceptable by the Court when (a) the circumstantial evidence runs parallel to the direct evidence available and the facts; and (b) the direct evidence is under the private control of the other party.
This decision may be contrasted with that in the Nicaragua Case, in which the Court concluded that in the absence of direct proof and presence of just circumstantial evidence, it could not be concluded that the majority of contra activities were backed by the United States.  The most important decision that needs to be considered, though, is the one in the Genocide Convention Case,  in which Serbia was allowed the use of secret documents to further its case, without producing the same in court.  Circumstantial evidence provided by Bosnia and Herzegovina to prove that Serbia itself had specific intent to commit genocide, but without specific reference to the circumstantial evidence, it was held that Serbia had failed to control and punish acts of genocide. Thus, circumstantial evidence was hardly relied upon, unlike in the Corfu Channel Case, and no liability was imposed on the basis of the same. Yet, the two decisions are similar as in both cases, the United Kingdom and Bosnia were permitted to produce circumstantial evidence. This was evaluated against the direct evidence provided by Albania and Serbia respectively, and the evidence provided by Serbia was deemed sufficient to counter the claims Bosnia had made on the basis of circumstantial evidence, while the same was not true for the evidence adduced by Albania.
There are further issues regarding evidence in the Court that need to be highlighted.
ADMISSIBILITY OF EVIDENCE
There are no particular rules binding the Court and parties when it comes to evidence, and the Court has not assumed a hierarchy of evidence or preferred one form of evidence over another.  The Court may call for evidence at any time  and has absolute freedom in estimating the value of evidence. Yet, it is apparent that the continental legal system has been adhered to, as written evidence is more common than oral evidence, but the use of oral testimonies of experts and witnesses is also mandated in the Statute and Rules of the Court.  Affidavits and sworn statements have also been admitted.  Additionally, certain provisions of the Rules govern written evidence. Article 50(1) of the Rules requires that “certified copies of any relevant documents adduced in support of the contentions claimed in the pleading" be attached to the pleading submitted to the Court. Moreover, as will be elaborated upon subsequently, Article 56 necessitates the consent of the court or the other party in order to adduce further documentary proof. Technical resources, like films, photographs and models may also be admitted and taken recourse to for determining facts by the Court.  The Court has felt able to take judicial notice of facts which are public knowledge, primarily through media dissemination, provided that caution was shown and that the reports did not emanate from a single source. 
Akin to all jurisdictions, evidence may be admitted not to prove a fact, but to corroborate the existence of a fact, as was done in the Nicaragua case, in which press articles and relevant excerpts from books were admitted. 
As has been mentioned earlier, Court procedure is liberal in nature, and the general tendency of the Court is to admit evidence rather than declare it inadmissible,  but there are certain circumstances in which the Court has declared, or is bound to declare, evidence inadmissible. Article 56 of the Rules declares that no further document may be submitted as evidence without the consent of the other party, after the written proceedings have concluded,  unless the Court, deeming it necessary, directs its production.  If such evidence is admitted, the other party is given the opportunity to comment on it and provide counter-documents.  Otherwise, the document in question shall not be referred to in proceedings and is deemed inadmissible.  Therefore, the procedural framework of the Court and decisions made  render evidence filed late, inadmissible. On certain occasions, the Court itself may determine the time within which the parties have to provide evidence for the determination of facts. Any evidence provided beyond the time prescribed may be considered inadmissible.  Additionally, evidence obtained through settlement negotiation is deemed inadmissible if the negotiation has been unsuccessful.  A prime example of the same is the Chorzów Factory Case,  in which the Court ignored the sum decided upon and calculations made during negotiations between Germany and Poland, when deciding the quantum of compensation to be awarded to Germany.  Some confusion still remains regarding whether evidence obtained by violation of international law is admissible, as happened in the Corfu Channel Case. The Court held that the act of the British Navy to carry out a minesweeping operation in Albanian waters violated the sovereignty of Albania, but failed to exclude the evidence that had been collected owing to the minesweeping operation. Therefore, with respect to unlawfully obtained evidence, it may be said that the practice of obtaining the evidence may be considered in violation of international law by the Court, but the evidence acquired may not be deemed inadmissible. This issue is rather contentious as two varying concerns are brought into conflict. On the one hand, there is a need to encourage the utilisation of the international adjudication system for violations of international law, but on the other, states may gather evidence with increased zeal, and therefore, may resort to illegal means to obtain proof for their contentions. Of course, as is customary in various jurisdictions, documents that are not authentic may also be declared inadmissible. 
BURDEN OF PROOF
When the question of allocating the burden of proof arises, the Court tends to apply the generally accepted principle of actori incumbit probatio, which means that it is up to the claimant to prove his claim. In other words, the party aiming to further a claim must establish its validity in fact and law. This has been repeatedly emphasised by the Court. In the Corfu Channel Case, as Britain was the plaintiff asserting its claim, it was subjected to the burden of proof.  Similarly, in the Nicaragua Case, the court stated that ‘ultimately…it is the litigant seeking to establish a fact who bears the burden of proving it’.  Therefore, despite the procedure and approach of the Court being quite flexible, the basic burden of proof remains that a person who asserts a fact must prove it.
The Court has mentioned that when it comes to jurisdiction, no particular burden of proof is to lie on either party and only if the same is refuted by one party will the burden of disproving jurisdiction exist.  Additionally, a relatively high burden lies on the applicant state which wants to intervene and the state ‘must demonstrate convincingly what it asserts, and thus…bear the burden of proof’. The state, though, has to just show that the interests of the state may being affected adversely, and not that the interests are or will actually be affected. This burden may be discharged if the state can successfully show how what the interest are, and how they are being affected.  This explains the complex way in which burden of proof and standard of proof, which shall be discussed subsequently, are intertwined.
There might be a division or distribution of the burden of proof, as was done in the Norwegian Loans Case,  which was a case before the Permanent Court of International Justice. In the case, it was stated that there is an onus on the party which raises the contention that local remedies have not been exhausted to prove before the Court that there are other domestic remedies which have not been used by the parties. Therefore, the burden shifts, prima facie, on the party attempting to prove the negative. If the Court takes judicial notice of certain facts averred, as they are of common knowledge or are self-evident, the burden of proving the same becomes non-existent.  Another case in which the burden shifts is when the Court makes a presumption in favour of a fact, leaving the party alleging the contrary to prove that the fact is not true.  The burden of proof to establish that a State was unable to exercise due diligence, or that an event took place despite the exercise of due diligence, lies with the State in control of such territory.  It is interesting to note that the burden of proof to prove that the burden of proof has shifted lies on the party on which the burden of proof existed naturally.
Therefore, when facts are agreed upon by parties, burden of proof is not an issue. The principle of actori incumbit probation applies generally. Otherwise, the Court decides on whom the burden lies. The Court may divide the burden of proof in relation to the facts on particular issues, as evidenced by the local remedies example, and this division is independent of the framing of the contentious issue by either party, but depends on how the court perceives this burden should stand.
STANDARD OF PROOF
The concept of an identifiable or quantifiable standard of proof emanates from the common law system, with its higher standard of “beyond reasonable doubt" in criminal proceedings, and the lower, more lenient standard of “by a preponderance of the evidence" in civil proceedings.  Again, the Court seems to be more influenced by the civil law scheme,  as the Court has to be persuaded of a claim and no particular standard is applicable.  In and subsequent to the Corfu Channel Case, various standards of proof have been employed.
Although proof beyond a reasonable doubt is usually employed as a standard in criminal proceedings, the Court has in some situations employed this standard and proof of facts to demonstrate a violation of human rights law by a state.  An equally high standard of proof appears to have been used in the Corfu Channel Case, as against the allegation by Britain that the minefield that had damaged British ships was laid with the knowledge and assistance of Albania, the Court concluded that an allegation of such seriousness would warrant a very high degree of certainty which could not be proved by Britain. 
A comparatively lower standard is demanded of the parties when the Court determines that a fact has to be proved in a convincing manner. The Nicaragua Case appears to be one in which such a standard has been applied. The only reference any the standard of proof in the Statute of the Court is in Article 53, which declares that if a party fails to appear in Court or defend its case, the Court, after satisfying itself that it has jurisdiction and the claim is “well founded in fact and law", shall rule in favour of the other party. The Court, in the case, elaborated on the provisions of Article 53(2),  saying that ‘satisfy itself’ means that the Court must attain a “degree of certainty", as in any other case, that the facts are based on convincing evidence.  Therefore, a standard lower than absolute proof beyond a reasonable doubt is provided for.
Some aspects of Court practice require even a prima facie proof of certain matters like jurisdiction in case of interim measures.  Such a standard was applied, or it is more fitting to say was excluded, in the Corfu Channel Case, when the Court held that “the mere fact of the control exercised by a state over its territory and waters…by itself and apart from other circumstances, neither involves prima facie responsibility nor shifts the burden of proof."  Therefore, it may be concluded that providing such standard of evidence shifts the burden of proof to the other party, yet, it must be determined whether, if the other party does not have the ability or means to discharge the burden, the prima facie evidence can be deemed a sufficient discharge of the burden. 
The standard of preponderance of evidence and that of reasonable conclusion have not found explicit mention in decisions by the Court, but for proving facts of relatively lesser importance, the Court appears to be willing to accept these standards, which fall between proof beyond reasonable doubt and proving facts in a convincing manner.  It is quite apparent that it is up to the Court to decide when it wants to apply what standard, and such decision is based on the facts and merits of the case at hand.
The decision in the Corfu Channel Case has been followed in subsequent decisions with respect to the use of circumstantial evidence and the standard of proof, but the Court has made minor changes in accordance with the facts of each case. Yet, in the Corfu Channel Case, instead of not declaring inadmissible the evidence acquired through unlawful means, the Court might have denied admissibility but imposed an onerous presumptio juris, effectively requiring Albania to demonstrate either that it could not have known of the mines or that it had used all due diligence in seeking to clear the Corfu Channel. Either technique would have affirmed the normative principle prohibiting the unlawful gathering of evidence, while still confirming Albanian liability. As things stand, the view of the Court on unlawfully obtained evidence remains unclear.
As more cases are decided by the Court, standards will evolve with respect to the burden and standard of proof and the admissibility of various kinds of evidence. Yet, as is apparent from the cases discussed, the Court has not hesitated to apply different standards based on the facts at hand. This is an acceptable trend as the primary reason why the procedure regarding evidence gives the Court such flexibility is that the nature of the cases presented before the Court require an especially broad tolerance, as the rights of nations and political equations are at stake. Therefore, the general consensus among practitioners and scholars is that stricter rules of admissibility of evidence are inappropriate for international adjudication. 
1. Michael P. Scharf and Margaux Day, Reconcilable Difference: A Critical Assessment of the International Court of Justice’s Treatment of Circumstantial Evidence 6, available at http://works.bepress.com/michael_scharf/2: This article provides an analysis of the general trend of the International Court of Justice in its approach towards the use of circumstantial evidence. The article covers cases from Corfu Channel to the Genocide Convention to discuss the levels of reliance the Court has placed on circumstantial evidence, and whether any change has occurred in the same since Corfu Channel was decided. The article is used to expand on the analysis of the Corfu Channel Case.
2. Eduardo Valencia-Ospina, Evidence Before the International Court of Justice, 1 Int’l L.F. D. Int’l 203 (1999): This article gives a broad overview of the procedure regarding evidence in the Court. The nature of the system, the issues discussed in this paper and recent developments are discussed briefly. The article is utilised to elaborate on the kinds of evidence used by the Court, the civil nature of the Court and burden of proof in case of jurisdiction.
3. Jens Evensen, Evidence Before International Courts, 25 Nordisk Tidsskrift Int’l Ret 44 (1955): This piece highlights the problems the Court (the Permanent Court of International Justice is extensively discussed) faces when it comes to evidence in international law. Documentary evidence, affidavits and other kinds of evidence are analysed in detail. The article is referred to with respect to how no particular kind of evidence is preferred over another and the standards of proof in civil proceedings.
4. W. Michael Reisman and Eric E. Freedman, The Plaintiff’s Dilemma: Illegally Obtained Evidence and Admissibility in International Adjudication, 76 (4) AJIL 737-753 (Oct., 1982): This article highlights how the Court system is influenced by civil law and why so. It goes on to discuss the grounds on which the Court may refuse to admit evidence. The issue of unlawful evidence is discussed extensively. The article is used to state that the general tendency of the Court is to accept all kinds of evidence and to reiterate the influence of civil law on the Court.
5. Neill H. Alford, Jr., Fact Finding by the World Court, 4 Vill. L. Rev. 37 (1959): This article again discusses how the Court functions with respect to deciding on facts. It provides an outline of the organization of the Court, allocation of the task of fact-finding, procedure regarding contentious cases and advisory cases, procuring and use of testimony, expert inquiries, rules of evidence and state security restrictions. The article is again used to refer to the influence of civil law on the Court.
1. Bin Cheng, general principles of law as applied by international courts and tribunals 303(2006).
2. Chittharanjan f. Amerasinghe, Evidence in International Litigation (2005).
3. Malcolm Shaw, international law (5th edn., 2004).
1. Corfu Channel Case (United Kingdom v. Albania), 1949 I.C.J. 4: The facts of the case are as discussed in the paper. The case is used to refer to the trend in accepting circumstantial evidence, shift of the burden of proof, proof beyond reasonable doubt and admissibility of illegally acquired evidence.
2. Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v. Serbia and Montenegro) 2007 I.C.J. 91: This case was filed as an aftermath of alleged Serbian attempts to wipe out the Bosnian Muslim population. The Court confirmed that genocide had occurred, but refused to pin responsibility on Serbia or make it an accomplice. Yet, Serbia was found in breach of international law and the Genocide Convention as it had failed to prevent the genocide and had not cooperated with the relevant Tribunal in punishing the perpetrators. The case is used to study the development of evidentiary rules regarding circumstantial evidence and to provide a comparison with the Corfu Channel Case.
3. Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America), Merits, 1986 I.C.J. 14: The case followed the revolt against the Nicaraguan government, which the government alleged, was backed by the United States. Also, there was apparent arms flow from Nicaragua to insurgents in El Salvador. There was insufficient evidence to show that either the Nicaraguan government or the United States was responsible for the same. The Court held that the United States had supported contra rebels in their fight against the Nicaraguan government, and therefore, was in violation of international law. The United States did not participate in the proceedings as a protest against the Court upholding its jurisdiction. The Court concluded that the United States was "in breach of its obligations under customary international law not to use force against another State", "not to intervene in its affairs", "not to violate its sovereignty", "not to interrupt peaceful maritime commerce", and also violated the Treaty of Friendship between the two countries. The case is used to define the scope of the decisions of the court, illustrate inadequacy of circumstantial evidence to prove a fact, discuss the inadmissibility of certain kinds of evidence, elaborate on general burden of proof and burden with respect to state intervention, and provide a basis for the interpretation of Article 53 of the Statute.
4. Chorzów Factory Case (Germany v. Poland), Merits, 17 PCIJ (Series A) 29, 51 (1928): The claim arose out of the expropriation of a factory by Germany in Poland. The Polish court declared German ownership to be illegal and gave the Polish treasury ownership. Germany then approached the Permanent Court International Justice, As the parties had agreed that Germany would not be given ownership, the issue of restitution was discussed. Poland argued that since previous ownership was illegal, no damages may be given. This was dismissed by the Court as ownership had previously been established. The Court held that “reparation must, as far as possible, wipe out all the consequences of the illegal act and re-establish the situation which would, in all probability, have existed if that act had not been committed." Therefore, Germany was granted damages. Yet, an out of court settlement was reached meanwhile. The case is used to illustrate that evidence obtained through settlement negotiation is deemed inadmissible if the negotiation has been unsuccessful
5. Fisheries Jurisdiction (Spain v. Canada), 87 I.C.J. 1998: Spain filed an application against Canada as a Canadian patrol boat had boarded a Spanish fishing vessel. The boarding was carried out under the Canadian Coastal Fisheries Protection Act. Canada claimed that the Court had no jurisdiction as it had included a reservation in its declaration of acceptance of the Statute of the Court excluding jurisdiction in some cases and the dispute referred to was included under the reservation. The Court accepted the arguments advanced by Canada and declared that it had no jurisdiction to adjudicate. The case is used to address the issue of burden of proof in case of jurisdiction of the Court.
6. Certain Norwegian Loans (France v. Norway), 9 I.C.J. 1957: The French government urged the Court to declare that certain loans and bonds issued on the French market and other markets by Norway could only be paid or redeemed if the borrower paid the requisite amount in gold. Norway contended that since it had issued the loans and bonds, all dispute would be settled by Norwegian courts, while the French wanted their courts to have jurisdiction. Therefore, on the matter of jurisdiction, the Court declared that it had no jurisdiction and the basis for jurisdiction is “the common will of the parties", and since the French and Norwegian declarations did not concur in granting jurisdiction, the Court lacked jurisdiction. The case is used to illustrate the shift of burden of proof in case of proving the exhaustion of local remedies.
documents of the international court of justice
Rules of the Court
Statute of the International Court of Justice