Wyo. Stat. § 37-2-209
No person shall be excused from testifying or from producing books, accounts and papers in any investigation or inquiry by or hearing before the commission or any commissioner, when ordered so to do, based upon or growing out of any violation of the provisions of this act, on the ground or for the reason that the testimony or evidence, documentary or otherwise, required of him may tend to incriminate him or subject him 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 he may have testified or produced any documentary evidence; provided, that no person so testifying shall be exempt from prosecution or punishment for perjury in so testifying.
W.S. 37-2-209