law: Indian Post Office Act, 1898 
  23. Power to deal with postal articles posted in
  
  contravention of Act
  (1) Any postal article
  
  sent by post in contravention of any of the provisions of this Act may be
  
  detained and either returned to the sender or forwarded to destination, in each
  
  case charged with such additional postage (if any) as the Central Government
  
  may by rule, direct.
  (2) Any officer in
  
  charge of post office or authorized by the Post Master General in this behalf
  
  may open or unfasten any newspaper or any book, pattern or sample packet, in
  
  course of transmission by post, which he suspects to have been sent by post in
  
  contravention of 17[section 20, clause (a), of] on section 21 or of
  
  any of the provisions of this Act relating to postage.
  (3) Notwithstanding
  
  anything in sub-section (1) -
  (a) any postal article sent by post in
  
  contravention of the provisions of section 19 15[or section 19A]
  
  may, under the authority of the Post Master General, if necessary, be opened
  
  and destroyed; and
   18  [(b) any postal article sent by post in
  
  contravention of the provisions of section 20 may be disposed of in such manner
  
  as the Central Government may by rule direct.]