Where the right to compel testimony is based upon a statute granting immunity from subsequent prosecution, the immunity granted must be complete. Absolute protection against later criminal actions for the offense to which the testimony relates must be provided. Thus in Counselman v. Hitchcock75 the court held with reference to testimony before the Interstate Commerce Commission, that immunity granted by Section 860 of the Revised Statutes providing that "no evidence given by the witness shall be in any manner used against him in any court of the United States, in any criminal proceeding" was insufficient in that, while it did prohibit the use of the testimony which might be given, it did not prevent a subsequent prosecution of the witness for the offense regarding which he might have been compelled to testify. In order to correct this deficiency in the law, Congress, by act of February 11, 1893,76 provided that, in the case designated, "no person shall be prosecuted or subjected to any penalty or forfeiture for or on account of any transaction, matter or thing, concerning which he may testify, or produce evidence, documentary or otherwise, before said Commission, or in obedience to its subpoena." 77

73 Burr's Trial. 244.

74 Brown v. Walker, 161 U. S. 591; 16 Sup. Ct. Hep. 644; 40 L. ed. 819. The converse of this, namely, that because the immunity granted by a state statute to prosecution does not extend to prosecutions in the federal courts the witness is not excused from testifying, is declared in Jack v. Kansas, 199 U. S. 372; 16 Sup. Ct. Rep. 73; 50 L. ed. 234. This doctrine is approved in Hale v. Henkel (201 U. S. 43; 26 Sup. Ct. Rep. 370; 50 L. ed. 652), the court saying: "Indeed, if the argument were a sound one, it might be carried still further and held to apply not only to state prosecutions within the same jurisdiction, but to prosecutions under the criminal laws of other States to which the witness might have subjected himself" The English doctrine is the same. See Wigmore on Evidence.

75 142 U. S. 547; 12 Sup. Ct. Rep. 195; 35 L. ed. 1110.

This law was upheld in Brown v. Walker.78