 In 1996 he was elected to serve on the United Nations International Law Commission; he was re-elected to the same position in 2001.On 7 November 2005 he was elected to a nine-year period as one of the judges of the International Court of Justice.In 2012, Sepúlveda-Amor was elected by the judges of the ICJ to serve as its vice-president, for a three-year term beginning 6 February 2012.