law: Custom Act, 1962 
  17.
  
  Assessment of Duty. – 
  (1)
  
  After an importer has entered any imported goods under section 46 or an exporter
  
  has entered any export goods under, section 50 the imported goods or the export
  
  goods, as the case may be, or such part thereof as may be necessary may,
  
  without undue delay, be examined and tested by the proper officer.
  (2)
  
  After such examination and testing, the duty, if any, leviable 
  
  on such goods shall, save as otherwise provided in section 85, be assessed.
  (3)
  
  For the purpose of assessing duty under sub-section (2), the proper officer may
  
  require the importer, exporter or any other person to produce any contract,
  
  broker's note, policy of insurance, catalogue or other document whereby the
  
  duty leviable on the imported goods or export goods,
  
  as the case may be, can be ascertained, and to furnish any information required
  
  for such ascertainment which it is in his power to produce or furnish, and
  
  thereupon the importer, exporter or such other person shall produce such
  
  document and furnish such information.
  (4)
  
  Notwithstanding anything contained in this section, imported goods or export
  
  goods may, prior to the examination or testing thereof, be permitted by the
  
  proper officer to be assessed to duty on the basis of the statements made in
  
  the enter relating thereto and the documents produced and the information
  
  furnished under sub-section (3); but if it is found subsequently on examination
  
  or testing of the goods or otherwise that any statement in such entry or
  
  document or any information so furnished is not true in respect of any matter
  
  relevant to the assessment, the goods may, without prejudice to any other
  
  action which may be taken under this Act, be re-assessed to duty.