law: Sashastra Seema Bal Act, 2007 
  13.  Restrictions respecting right to form
  
  association, freedom of speech, etc.
  1.       No
  
  person subject to this Act shall, without the previous sanction in writing of
  
  the Central Government or of the prescribed authority.
  a.       be a
  
  member of, or be associated in any way with, any trade union, labour union,
  
  political association, or with any class of trade unions, labour unions or
  
  political associations; or
  b.      be a
  
  member of, or be associated in any way with, any society, institution,
  
  association or organisation which is not recognised as part of the Force or is
  
  not of a purely social, recreational or religious nature; or
  c.       communicate
  
  with the press or publish or cause to be published any book, letter or other
  
  document except where such communication or publication is in the bona fide discharge
  
  of his duties or is of a purely literary, artistic or scientific character or
  
  is of a prescribed nature.
   Explanation..  If any question arises as to
  
  whether any society, institution, association or organisation is of a purely
  
  social, recreational or religious nature under clause (b ) of this
  
  sub-section, the decision of the Central Government thereon shall be final.
  2.       No
  
  person subject to this Act shall participate in, or address, any meeting or
  
  take part in any demonstration organised by anybody of persons for any
  
  political purposes or for such other purposes as may be prescribed.