The 10th Schedule to the Constitution, popularly referred to as the ‘Anti-Defection Law,' was inserted by the 52nd Amendment in 1985.
The grounds of disqualification are specified in Paragraph 2 of the 10th Schedule.
A member would incur a disqualification under paragraph 2 (1) (a) when he “voluntarily gives up his membership of a party” and under 2 (1) (b) when he/she votes (or abstains from voting) contrary to the directive issued by the party.
Two important questions arise in this regard: what would constitute the member ‘voluntarily' giving up of membership of a party? And, what is the full import of 2 (1) (b), wherein voting/abstention from voting against the party is mentioned?
The Supreme Court, in the Ravi Naik vs. Union of India case, has interpreted the phrase ‘voluntarily gives up his membership.' It says: “The words ‘voluntarily gives up his membership' are not synonymous with ‘resignation' and have a wider connotation. A person may voluntarily give up his membership of a political party even though he has not tendered his resignation from the membership of that party.
“Even in the absence of a formal resignation from membership, an inference can be drawn from the conduct of a member that he has voluntarily given up his membership of the political party to which he belongs.”
In another judgment in the case of Rajendra Singh Rana vs. Swami Prasad Maurya and Others, the Supreme Court held that the act of giving a letter requesting the Governor to call upon the leader of the other side to form a Government itself would amount to an act of voluntarily giving up membership of the party on whose ticket the said members had got elected.