Nebraska Revised Statute 53-180.07
Minors; licensee charged with sale; defenses.
In any prosecution of or any proceeding against any licensee charged with having made a sale to a minor, proof of the following shall be an absolute defense to the charge:
(1)(a) The purchaser falsely represented in writing and supported with other documentary proof that he or she was of legal age to purchase alcoholic liquor;
(b) The appearance of such purchaser was such that an ordinary and prudent person would believe that such appearance conformed to any documentary description of appearance presented by the purchaser; and
(c) The seller was acting in good faith, in reliance upon the written representation, other documentary evidence, and the appearance of the purchaser, and in the belief the purchaser was of legal age to make such purchase; or
(2) The seller was acting with the knowledge of and in cooperation with a duly authorized law enforcement officer.