51. Bar of suits, prosecution and other legal proceedings.-- 

(1)    No suit shall he brought in any Civil Court to set aside or modify any order passed, any assessment made,
any tax levied, any penalty imposed or collection of any tax made under this Act.
       
(2)    No suit, prosecution or other legal proceeding shall lie against the Federal Government or against any public
servant in respect of any order passed in good faith under this Act.
 
(3)    Notwithstanding anything in any other law for the time being in force, no investigation or inquiry shall be
undertaken or initiated by any governmental agency against any officer or official for anything  done in his official
capacity under this Act, rules, instructions or direction made or issued thereunder without the prior approval of the Board.