§702-220 Ignorance or mistake of law; belief that conduct not legally prohibited. In any prosecution, it shall be an affirmative defense that the defendant engaged in the conduct or caused the result alleged under the belief that the conduct or result was not legally prohibited when the defendant acts in reasonable reliance upon an official statement of the law, afterward determined to be invalid or erroneous, contained in:
(1) A statute or other enactment;
(2) A judicial decision, opinion, or judgment;
(3) An administrative order or administrative grant of permission; or
(4) An official interpretation of the public officer or body charged by law with responsibility for the interpretation, administration, or enforcement of the law defining the offense. [L 1972, c 9, pt of §1; am L 1973, c 136, §3(b); gen ch 1993]