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Alok Verma was stripped of his powers days after he launched an investigation into corruption allegations against his deputy Rakesh Asthana, accused of taking bribe in an investigation against a businessman.
Rakesh Asthana, CBI's Special Director, fired back at his boss with the same charge, alleging it was Mr Verma who had taken bribe from the same businessman.
On Tuesday, Rakesh Asthana took the CBI to court and asked for the CBI's case against him to be dropped. He was then divested of all his powers and sent on leave. Hours later, the government decided on similar action against the CBI chief, on a recommendation from the Central Vigilance Commission -- the anti-corruption body that oversees the CBI. "Neither of the two officers, nor any agency under their supervision can investigate charges against them," the vigilance body said, explaining why the CBI chief must also go.
Interim CBI chief M Nageswar Rao, who took charge around 2 am, signed off on orders the same night to transfer a dozen officers on Mr Verma's team, including those investigating Mr Asthana.
Senior jurist Fali Nariman, 89, will represent Mr Verma in the Supreme Court; Attorney General KK Venugopal will represent the centre; Solicitor General Tushar Mehta will appear for the Central Vigilance Commission, and former Attorney General Mukul Rohatgi will appear for Rakesh Asthana.
Mr Verma argues in his petition that the Supreme Court had ruled in the past that the CBI director should have a fixed minimum tenure of two years. His petition also says Mr Asthana "concocted evidence" against him to accuse him of corruption.
The CBI on Thursday clarified that both Mr Verma and Mr Asthana retain their posts. Mr Rao will remain interim chief till the main anti-corruption body, the Central Vigilance Commission, examines the allegations swapped by the top two officers.
The Congress has accused the government of "violating the law, the Supreme Court's clear directions on the subject and the Constitution of India". The Congress said the CBI chief can't be removed without the approval of a group that includes the Prime Minister, Chief Justice of India and the Leader of the Opposition in parliament.
The Congress has planned a protest at the CBI headquarters today to highlight what it calls the "CBI's slumping credibility". Congress chief Rahul Gandhi tweeted that he would lead the protest.
On Thursday, four Intelligence Bureau officials lurking near the banished CBI chief's home were caught and dragged by his security officers and accused of snooping on Mr Verma. Stung by footage of its officials being dragged and pushed, the Intelligence Bureau objected to how its personnel were treated on a "routine patrol".
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