In the United States v. Hoffman case of 1947, the Supreme Court ruled that a bankruptcy referee did not have the authority to grant immunity from prosecution to a witness who refused to answer questions on grounds of self-incrimination. The defendant, Louis Hoffman, was called as a witness in an involuntary bankruptcy proceeding and declined to answer certain questions citing his Fifth Amendment rights against self-incincrimination. The court-appointed referee ordered him to respond under threat of contempt charges but promised he would not be prosecuted based on his answers. When Hoffman continued refusing, he was found guilty for contempt by district courts and later by appellate courts too. The Supreme Court reversed these decisions stating that only Congress has power over granting immunities; it cannot be exercised by judicial officers or tribunals without explicit statutory authorization. They further clarified that while witnesses can't simply refuse questioning altogether using Fifth Amendment protections, they are allowed this right when there's reasonable cause for fear of prosecution.

In the dissenting opinion for United States v. Hoffman, Justice Murphy argued that the majority's decision to uphold contempt charges against a witness who refused to answer questions before a grand jury on grounds of self-incrimination was incorrect. He contended that this ruling violated the Fifth Amendment rights of witnesses by forcing them into an impossible situation where they must either incriminate themselves or face punishment for contempt. Furthermore, he criticized the majority’s reliance on Mason v. United States as precedent since it involved different circumstances and thus should not be applied in this case. In his view, any question posed to a witness which could potentially lead to criminal prosecution should fall under their right against self-incincrimination regardless if it is directly related or not with ongoing investigations.