Since the C-400-98 decision, the Colombian Constitutional Court adopted for the first time the thesis of moderate monism, as a theory to orientate the relationship between international law and domestic law. This judicial decision supported its theory on Alfred Verdross’ doctrine, who according to the Court is the leading author of moderate monism. This article will analyze the theoretical and doctrinal support of the theory advocated by the Court, based on the original theory of Verdross. To do this, the article will analyze the proposal of the Constitutional Court; then, it will present a summary of the theories that explain the relationship between International and domestic law, chiefly the genuine moderate monism. Next, after comparing the Constitutional Court’s and the original theory of Verdross, it will be demonstrated that the Colombian Tribunal distorted moderate monism, which casts a shadow of doubt on the soundness of the theoretical foundation assumed by the Court. This will lead to conclude that Colombia has never accepted the moderate monism theory and therefore it is necessary to abandon such doctrinal reference and modify the existing precedent.