Recurring defections among legislators from parties including Shiv Sena (UBT) and Trinamool Congress have revived debate on the effectiveness of India's anti-defection law.

Defection is governed by the Tenth Schedule (inserted via the 52nd Constitutional Amendment, 1985), with disqualification criteria under Articles 102(2) and 191(2).

The 91st Amendment (2003) abolished the one-third split exception; a merger now needs at least two-thirds of a legislature party's members to avoid disqualification.

Critics point to the partisan role of Speakers in deciding disqualification petitions and the 'merger loophole' as key weaknesses undermining the law's intent.