76-1-502. Negating defense by allegation or proof -- When not required.
Sectiondoes not require negating a defense:
(1) By allegation in an information, indictment, or other charge; or
(2) By proof, unless: The defense is in issue in the case as a result of evidence presented at trial, either by the prosecution or the defense; or The defense is an affirmative defense, and the defendant has presented evidence of such affirmative defense.