Blau v. United States

Petitioner was summoned to appear before a federal district grand jury in Denver, Colorado. Both before that body and before the district judge where he was later taken, petitioner declined to answer questions concerning the activities and records of the Communist Party of Colorado, claiming his constitutional privilege against self-incrimination. He also refused to reveal the whereabouts of his wife, who was wanted by the grand jury as a witness in connection with the same investigation. As to this refusal to testify, petitioner asserted his privilege against disclosing confidential…