A person who obtains any information in the course of or arising out of the business of preparing or assisting in the preparation of a tax return of another person, shall not disclose any of the information obtained unless the disclosure is within any of the following:
1. Consented to in writing by the taxpayer in a separate document.
2. Expressly authorized by state or federal law.
3. Necessary to the preparation of the return.
4. Pursuant to court order.
C2005, §421A.2