New Delhi, 22 Jan

The CBI will file an appeal before the Calcutta High Court, seeking death sentence for Sanjay Roy, who was sentenced to "life imprisonment until death" by a Sealdah court in the rape-cum-murder case of an on-duty doctor at RG Kar Medical College and Hospital, officials said Wednesday.

The agency received a legal advice suggesting that the case may be categorised as the "rarest of rare", deserving capital punishment, they said.

The agency is likely to file the appeal against the Sealdah court order as soon as possible with detailed arguments in favour of capital punishment, they said.

The agency's plea seeking death penalty for Roy was turned down by the trial court, where Additional District and Sessions Judge Anirban Das said that the crime did not fall under the "rarest of the rare" category.

"The CBI prayed for the death penalty. The defence lawyer prayed that a jail term be given instead of the death penalty. This crime does not fall under the 'rarest of the rare' category," the judge said on Monday while sentencing Roy.

"I am sentencing you to life imprisonment, meaning till the last day of your life, for causing injury during the act of committing rape on the victim that led to her death...," he told Roy.

The West Bengal government has already approached the high court, challenging the verdict and seeking death penalty for Roy.

The CBI has opposed the state's right to file an appeal in the case, claiming that as it was the prosecuting agency, it had the right to appeal on the grounds of inadequacy of the sentence.

Appearing for the CBI, Deputy Solicitor General Rajdeep Majumdar on Wednesday opposed the state's submission, maintaining that the West Bengal government does not have the right to appeal against the trial court's order on the ground of inadequacy.

He submitted that the CBI had prayed for awarding capital punishment to Roy before the trial court.

The high court said it would hear the CBI, the victim's family and the convict before deciding on the admission of the state government's appeal. The high court said it will hear the matter on January 27.

The trainee doctor was raped and killed in the early hours of August 9 in the seminar hall of RG Kar Medical College and Hospital when she had gone to have rest during her graveyard shift.

Her body with severe injury marks was found inside the hall by a doctor next morning.

Civic volunteer Sanjay Roy was arrested the next day based on CCTV footage in which he was seen entering the seminar hall at 4.03 am on the day of the incident.

On August 13, the Calcutta High Court ordered the transfer of the probe from Kolkata Police to the CBI, which took over the case on August 14.