From 1993 to 1998, he was United States Assistant Secretary of State for Democracy, Human Rights and Labor under President Bill Clinton, where he played a key role in the establishment by the United Nations of the International Criminal Tribunals for Rwanda and former Yugoslavia, working closely with Secretary of State Madeleine Albright. In 1995, he was the first international diplomat to reach survivors of the Srebrenica genocide in Bosnia, assembling evidence for the UN Security Council vote authorizing NATO intervention in Bosnia. During this tenure, he visited Chinese dissident Wei Jingsheng and the Chinese government used the meeting as a pretext to arrest Wei and re-imprison him.