This essay analyzes the practice of addressing counter-claims before the International Court of Justice (ICJ), as well as its predecessor, the Permanent Court of International Justice (PCIJ). In the Court’s jurisprudence, a “counter-claim” is an autonomous legal act by the respondent in a contentious case before the Court, the object of which is to submit a new claim to the Court, one that is linked to the principal claim. A counter-claim is not a defense on the merits to the principal claim; while it is a reaction to that claim, it is pursuing objectives other than simply dismissal of the principal claim. Hence, the reason for allowing a counter-claim to be included as part of an existing case is not because it assists in disposition of the principal claim but, rather, to assist in the disposition of two autonomous claims.
The ICJ Statute does not directly address the issue of the respondent filing a counter-claim against the applicant. Article 80 of the Rules of the Court, however, provides that the Court may entertain such a counter-claim provided two requirements are met: the counter-claim falls within the jurisdiction of the Court; and it is directly connected with the subject matter of the principal claim. The Court’s case law has developed the contours of such requirements, as well as the procedures used in filing and assessing them. While counter-claims featured somewhat during the time of the PCIJ, and in the early life of the present Court (in 1950–1952), use of them disappeared for several decades, only re-emerging in several cases after 1997, most recently in Alleged Violations of Sovereign Rights and Maritime Spaces in the Caribbean Sea (Nicaragua v. Colombia). Renewed interest in the filing of counter-claims may be due to a desire by respondents to present to the Court a more balanced perspective of the conduct of the two States before it, since inclusion of a counter-claim may force both the Court and the other party to confront certain facts and legal arguments that otherwise would not feature in the case.
GW Paper Series
GWU Law School Public Law Research Paper No. 2017-85; GWU Legal Studies Research Paper No. 2017-85
Murphy, Sean D., Counter-claims, in The Statute of the International Court of Justice - A Commentary, Andreas Zimmerman and Christian J Tams, eds., 3d ed., Oxford University Press (forthcoming).