Admissibility of statements made before a gazetted excise officer when a witness is unavailable or justice requires admission. A signed statement made before a gazetted Central Excise Officer is admissible in prosecution to prove facts where the maker is unavailable-dead, cannot be found, incapable, kept away by an adverse party, or where attendance would cause unreasonable delay or expense-and may also be admitted if the maker is examined and the Court, in the interests of justice, permits it. These relevancy rules apply, so far as practicable, to proceedings under the Act other than before a Court.