When the Constitutional Court reviews the constitutionality and conventionality of laws, it declares their adequacy or inadequacy to the principles, rights and norms enshrined in the Constitution and in the American Convention on Human Rights, developing a fairly complex “legal” action, to the extent that –in many cases– it intervenes in policy areas of the legislator himself. This situation creates tension between the legislative power and the judicial power, as it is argued that the latter was not popularly elected, as it is with the legislator. Therefore, this research aims at describing these tensions in the context of control of constitutionality and conventionality over the laws in Colombia. Highlighting the importance of the latter as a kind of concurrent, complementary and necessary control of constitutionality. For this, a theorizing exercise is carried out based on bibliographic review and illustrations with rulings, presented with a qualitative approach.