law: Prevention of Cruelty to Animals Act, 1960
  30. Presumption as to guilt in certain cases. -
  If any person is charged with the offence of
  
  killing a goat, cow or its progeny contrary to the provisions of clause (l) of
  
  sub-section (1) of section 11, and it is proved that such person had in his
  
  possession, at the time the offence is alleged to have been committed, the skin
  
  of any such animal as is referred to in this section with any part of the skin
  
  of the head attached thereto, it shall be presumed until the contrary is proved
  
  that such animal was killed in a cruel manner.