Anti-Defection Law

The Tenth Schedule — popularly known as the Anti-Defection Act — was included in the Constitution in 1985 by the Rajiv Gandhi ministry and sets the provisions for disqualification of elected members on the grounds of defection to another political party. The law was added via the 52nd Amendment Act, 1985

Ground for disqualification:
a) If an elected member voluntarily gives up his membership of a political party.
b) If he votes or abstains from voting in such House contrary to any direction issued by his political party or anyone authorised to do so, without obtaining prior permission. As a pre-condition for his disqualification, his abstention from voting should not be condoned by his party or the authorised person within 15 days of such incident.

Loopholes:
a) As per the 1985 Act, a ‘defection’ by one-third of the elected members of a political party was considered a ‘merger’.
Finally the 91st Constitutional Amendment Act, 2003, changed this. So now at least two-thirds of the members of a party have to be in favour of a "merger" for it to have validity in the eyes of the law.
b)Court has no jurisdiction on this matter. Speakers decides it