Oregon Revised Statutes Utility Regulation § 756.552

No person shall be excused from testifying or from producing books and papers in any court proceeding based upon or growing out of any violation of the provisions of ORS chapter 756, 757, 758, 759 or 825 or ORS 824.020 to 824.042, 824.050 to 824.110, 824.200 to 824.256 or 824.300 to 824.310 on the ground or for the reason that the testimony or evidence, documentary or otherwise, required of the person may tend to incriminate the person or subject the person to penalty or forfeiture; but no person having so testified shall be prosecuted or subjected to any penalty or forfeiture for, or on account of, any transaction, matter or thing concerning which the person may have testified or produced any documentary evidence. However, no person shall be exempted from prosecution or punishment for perjury while so testifying. The immunity conferred by this section shall extend only to a natural person who, in obedience to a subpoena, gives testimony under oath or produces evidence, documentary or otherwise, under oath.