PART I - GENERAL PROVISIONS
ARTICLE 2. GENERAL PRINCIPLES OF LIABILITY

§2.04. Ignorance or Mistake.
(1) Ignorance or mistake as to a matter of fact or law is a defense if:
(a) the ignorance or mistake negatives the intent, purpose, knowledge, belief, recklessness or negligence required to establish a material element of the offense; or
(b) the law provides that the state of mind established by such ignorance or mistake constitutes a defense.
(2) Although ignorance or mistake would otherwise afford a defense to the offense charged, the defense is not available if the defendant would be guilty of another offense had the situation been as the defendant supposed. In such case, however, the ignorance or mistake of the defendant shall reduce the grade and degree of the offense of which the defendant may be convicted to those of the offense of which he or she would be guilty had the situation been as he or she supposed.
(3) A belief that conduct does not legally constitute an offense is a defense to a prosecution for that offense based upon conduct when:
(a) the offense is a violation of an administrative regulation or order, and the regulation or order is not known to the actor and was not reasonably available prior to the conduct alleged; or
(b) the person acts in reasonable reliance upon an official statement of the law, afterward determined to be invalid or erroneous, contained in:
(i) a statute or other enactment;
(ii) a judicial decision, opinion or judgment;
(iii) an administrative order or grant of permission; or
(iv) an official interpretation of the public officer or body charged by law responsibility for interpretation, administration or enforcement of the law defining the offense.