The Formal Sources of International Law, the Relationship between Treaties and Custom, and the International Law-Making Process


James Crawford in his Hague general course on public international law discussed the problem of making international law by treaties under the Baxter paradox—“the more agreement, the less law”. Crawford concluded that the Baxter paradox is not so much an insoluble paradox as a valid reflection on the distinct attributes of treaties and custom—something to be embraced and not avoided. The essay seeks to readdress the relationship between treaties and custom taking into account the Baxter paradox and its critical examination by Crawford. It is also discussed in light of the complex problem of exploitation of outer space natural resources.
The author supports the idea of formal sources as the most workable method of analyzing rules and principles of international law in practice. The primary aim of the article is to consider whether treaties can be seen, as most scholars claim, the formal source of international law. The author argues that they are not of that nature, since they are not the self-sufficient source of general international law. The author is inspired by Gerald Fitzmaurice’s views of the 1950s denying treaties the status of formal sources of international law, instead seeing them merely as sources of international legal obligations. According to the author, these views, although controversial and even outmoded under the contemporary opinions on the sources of international law, still deserve attention and careful consideration. Treaties can promote legal certainty with regard to legal obligations within the international community. Yet, as the author claims, in a decentralized legal order such as international law, it is not treaties but custom that still remains its primary formal source.