Except as otherwise expressly provided, a person's good faith belief that conduct does not constitute a crime is an affirmative defense if he acted in reasonable reliance upon a statement of the law contained in:
1. A statute or other enactment.
2. A judicial decision, opinion, order, or judgment.
3. An administrative order or grant of permission.
4. An official interpretation of the public servant or body charged by law with responsibility for the interpretation, administration, or enforcement of the law defining the crime.