law: 34. Official language or languages of the Capital and languages or languages to be used in Legislative Assembly.-
  (1) The Legislative Assembly may by law adopt any one or more of the languages in use in the Capital or Hindi as the official language or languages to be used for all or any of the official purposes of the Capital:  Provided that the President may by order direct-
  (i) that the official language of the Union shall be adopted for such of the official purposes of the Capital as may be specified in the order;
  (ii) that any other language shall also be adopted throughout the Capital or such part thereof for such of the official purposes of the Capital as may be specified in the order, if the President is satisfied that a substantial proportion of the population of the Capital desires the use of that other language for all or any of such purposes.
  (2) The business in the Legislative Assembly shall be transacted in the official language or languages of the Capital or in Hindi or in English: Provided that the Speaker of the Legislative Assembly or person acting as such, as the case may be, may permit any member who cannot adequately express himself in any of the languages aforesaid to address the Assembly in his mother-tongue.