The Indian Succession Act,1925
Section 127. Bequest upon illegal or immoral condition
A bequest upon a condition, the fulfilment of which would be contrary to law or to morality is void.
Illustrations
(i) A bequeaths 500 rupees to B on condition that he shall murder C. The bequest is void.
(ii) A bequeaths 5,000 rupees to his niece if she will desert her husband. The bequest is void.