Any defendant, or any witness, in any civil action brought under the provisions of this Subpart may be required to testify, and the books, records, invoices and all other documents of any defendant, may be brought into court and introduced as evidence, but no defendant, or any witness in any civil action 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, and no testimony given or produced shall be received against him upon any criminal proceeding or investigation.
La. R.S. § 51:425