Senior Advocate and Rajya Sabha member Kapil Sibal has moved the Supreme Court challenging the constitutional interpretation of the Tenth Schedule's Paragraph 4, arguing that the existing legal position on political mergers is systematically hollowing out India's anti-defection law. The writ petition, filed by Sibal as a party-in-person against the Union of India, was assigned Diary No. 42846/2026 and registered on 20 July 2026.

What Sibal Argued Before the Court

Mentioning the matter before a Bench headed by Chief Justice of India Surya Kant, Sibal pressed for an early hearing. He told the Bench: 'I have filed a petition in person. It relates to the issue of whether the composition of the Parliament can change in the fashion in which it is happening in this country and the interpretation of the Tenth Schedule, Paragraph 4, in that context.'

Sibal warned that if the current trend of political mergers continued unchecked, the Tenth Schedule would be rendered meaningless. 'What is happening in this country? If this continues, the Tenth Schedule will become meaningless,' he submitted. CJI Kant assured the court that the matter would be listed for hearing.

The Legal Challenge: Merger Route as a Defection Shield

At the core of Sibal's petition is a challenge to how Paragraph 4 of the Tenth Schedule — which provides an exemption from disqualification in the event of a party merger — is being interpreted and applied. He contends that splinter groups of legislators are exploiting this provision to evade disqualification by engineering mergers with rival parties, thereby defeating the very purpose for which the anti-defection law was enacted.

The Tenth Schedule, introduced via the 52nd Constitutional Amendment in 1985, was designed to deter floor-crossing and ensure legislative stability. Critics argue, however, that the merger exemption has over time become a favoured instrument for orchestrated defections dressed up as legitimate political realignments.

Shiv Sena (UBT) Case: A Parallel Battle

Sibal noted that a related matter filed by Shiv Sena (UBT) was already pending before the apex court — a reference that underscores the broader pattern his petition seeks to address. Separately, the Supreme Court is scheduled to hear a plea by Shiv Sena (UBT) MP Arvind Sawant, challenging Lok Sabha Speaker Om Birla's decision to recognise the merger of six Shiv Sena (UBT) MPs with the Eknath Shinde-led Shiv Sena.

That petition, listed before a Bench of Justices P.S. Narasimha and Alok Aradhe, contends that the Speaker's recognition of the merger has severely damaged Shiv Sena (UBT)'s parliamentary presence — reducing its Lok Sabha strength from nine MPs to three.

Broader Context: A Pattern of Opposition Defections

Sibal's petition arrives amid a series of defections and mergers involving legislators from Opposition parties, a trend that has accelerated in recent months. This is not an isolated legal challenge; it is part of a growing body of litigation questioning how constitutional safeguards against defection are being applied — or circumvented — in practice.

Notably, the Supreme Court's landmark 2023 ruling in the Shiv Sena dispute had flagged concerns about the Speaker's role in adjudicating disqualification petitions, yet the merger exemption itself was not conclusively settled. Sibal's petition now squarely targets that gap. With multiple such cases queued before the apex court, a definitive constitutional ruling on Paragraph 4 could reshape the rules of political realignment across India.