law: Code of Criminal Procedure Act, 1973
  
  298.Previous conviction or acquittal how proved.-
  In any inquiry, trial or other proceeding
  
  under this Code, a previous conviction or acquittal may be proved, in addition
  
  to any other mode provided by any law for the time being in force, -
  (a) by an extract certified under the hand of the officer having the custody of
  
  the records of the Court in which such conviction or acquittal was held, to be
  
  a copy of the sentence or order, or
  (b) in case of a conviction, either by a certificate signed by the officer in
  
  charge of the jail in which the punishment or any part thereof was undergone,
  
  or by production of the warrant of commitment under which the punishment was
  
  suffered, together with, in each of such cases, evidence as to the identity of
  
  the accused person with the person so convicted or acquitted.