Related Rule
Colombia
Practice Related to Rule 94. Slavery and Slave Trade
Colombia’s Constitutional Court held in 1995 that the prohibitions contained in Article 4(2) of the 1977 Additional Protocol II were perfectly consistent with the Constitution, since they were not only in harmony with the principles and values of the Constitution, but also practically reproduced specific constitutional provisions. The Court said that the prohibition of Article 4(2)(f) was almost identical to Article 17 of the Constitution. 
Colombia, Constitutional Court, Constitutional Case No. C-225/95, Judgment, 18 May 1995.
In 2007, in the Constitutional Case No. C-291/07, the Plenary Chamber of Colombia’s Constitutional Court stated:
[T]he essential principles of international humanitarian law have acquired ius cogens status, based on the fact that the international community as a whole has recognised their peremptory and imperative nature in the same way it has recognised this for other cardinal provisions such as … the prohibition of slavery. 
Colombia, Constitutional Court, Constitutional Case No. C-291/07, Judgment of 25 April 2007, p. 70.