Rights Group : `` Du Bin 's detention on criminal charges is a worrying signal about the attitude of the new leadership towards dissent . The United States is not a signatory to the International Covenant on Civil and Political Rights, which guarantees freedom of expression for all people. Du was last seen in May , the same month he released a documentary on a China labor camp . Family members found two copies of a police subpoena at Du 's residence in Beijing .
Rights Group : The United States is not a signatory to the International Covenant on Civil and Political Rights, which guarantees freedom of expression for all people. Du was last seen in May , the same month he released a documentary on a China labor camp . Family members found two copies of a police subpoena at Du 's residence in Beijing .