Trinamool Congress (TMC), led by Mamata Banerjee, has moved the Supreme Court challenging Lok Sabha Speaker Om Birla's inaction on disqualification petitions filed against 20 rebel party MPs. The writ petition, filed through TMC national general secretary and Diamond Harbour Lok Sabha member Abhishek Banerjee, is listed for hearing on 25 August 2026 before a Bench headed by Chief Justice of India (CJI) Surya Kant, along with Justices Joymalya Bagchi and V. Mohana.

What the Petition Argues

The writ petition, registered as W.P.(C) No. 1033/2026, challenges the prolonged delay in deciding disqualification proceedings initiated under the anti-defection law. The TMC contends that the 20 MPs were elected on the party's symbol and their subsequent decision to join another political formation — the Nationalist Citizens Party of India (NCPI) — squarely attracts disqualification under the Tenth Schedule of the Constitution.

The respondents named in the petition include the Speaker of the Lok Sabha, the Secretary General of the Lok Sabha, and the 20 rebel MPs: Kakoli Ghosh Dastidar, Sudip Bandyopadhyay, Satabdi Roy, Prasun Banerjee, Rachana Banerjee, Jagadish Chandra Barma Basunia, Partha Bhowmick, Arup Chakraborty, Adhikari Deepak Dev, Sayani Ghosh, Bapi Haldar, Md Abu Taher Khan, Kalipada Saren Kherwal, Asit Kumar Mal, June Maliah, Mitali Bag, Khalilur Rahaman, Mala Roy, Sharmila Sarkar, and Pathan Yusuf.

Background: How the Split Unfolded

The crisis within the TMC's parliamentary unit escalated after the 20 MPs broke away and joined the NCPI, claiming recognition as a separate parliamentary group. The rebel faction asserted it had the support of more than two-thirds of TMC's Lok Sabha MPs — a threshold that, under Paragraph 4 of the Tenth Schedule, could potentially shield them from disqualification through the merger provision.

The TMC, however, has argued that crossing the two-thirds threshold alone does not satisfy the merger provision's requirements, and that voluntarily relinquishing party membership to join another formation still invites disqualification. Notably, separate seating arrangements were allotted to the rebel MPs in the Lok Sabha even as the Speaker had not formally ruled on the disqualification petitions — a development the TMC viewed as premature recognition.

Jagadish Chandra Barma Basunia, one of the rebel MPs, had stated that the group sought to stake a claim as the 'real Trinamool Congress' and secure independent recognition in the lower house.

Repeated Attempts to Expedite Action

Abhishek Banerjee had previously filed separate disqualification petitions before Speaker Om Birla and repeatedly pressed for their swift disposal. On 27 July, he again wrote to the Speaker urging expeditious action. TMC leaders including Mahua Moitra and Kalyan Banerjee had also met the Speaker to demand immediate proceedings.

In July, West Bengal Chief Minister Suvendu Adhikari travelled to New Delhi to meet the rebel MPs, who had aligned with the NCPI and declared support for the ruling National Democratic Alliance (NDA) at the Centre — adding a distinct political dimension to what was already a fraught constitutional dispute.

The Larger Constitutional Question

The Supreme Court is separately seized of a broader constitutional question on the interpretation of the anti-defection law. Senior advocate Kapil Sibal has moved the court as a party-in-person, challenging the interpretation of Paragraph 4 of the Tenth Schedule, which governs party mergers. Sibal has argued that the existing legal position allows splinter groups to evade disqualification by routing defections through mergers, thereby diluting the very purpose of the anti-defection framework.

The outcome of the disqualification proceedings is expected to carry significant political and constitutional implications — not only for the TMC and its rebel MPs, but for the broader question of how the anti-defection law applies to large-scale legislative splits.