NEW DELHI: The Centre on Sunday told the Delhi high court that the four death row convicts in Nirbhaya case are "not entitled" to any more time, as it cited the 2019 gangrape and murder of a Hyderabad vet in which the four accused were killed by police in an alleged encounter and asserted that the credibility of the judiciary and its own power to execute death sentence are at stake.

Solicitor General Tushar Mehta, representing the Centre and Delhi government which have sought setting aside of a trial court order staying the execution of convicts in 2012 Nirbhaya gangrape-murder case, said that there is a deliberate, calculated and well thought of design to "frustrate mandate of law" by the convicts who were "trying the patience of the nation".

Justice Suresh Kait reserved the order on the joint plea by the Centre and Delhi government after a three-hour hearing, during which senior advocate Rebecca John, representing convict Mukesh Kumar, contended that since the four were sentenced to death by a common order, they have to be executed together and cannot be "singled out".

"Let me concede I have delayed the process, I am a worst person, I have committed a horrible crime which is unimaginable, still I am entitled to Article 21 (right to life) of the Constitution," John submitted.

During his arguments, Mehta contended that convict Pawan Gupta's move of not filing a curative or a mercy petition is a deliberate, calculated inaction.

He said there was a deliberate delay on the part of the convicts and a prompt reaction to their pleas by the judicial and executive system.

The law officer said by the trial court's interpretation of Rules, if convict Pawan Gupta chooses not to file mercy plea, then nobody could be hanged.

"There is a deliberate move of co-convicts to delay the process which can frustrate the mandate of the trial court's judgment awarding them death sentence that was confirmed by the Delhi high court and upheld by the Supreme Court," he said.

Referring to the December 6, 2019 Hyderabad gangrape and murder case of a veterinarian in which the four accused were killed by the police in an alleged encounter, the Solicitor General said what happened there was shocking but people celebrated it.

"It gave a very bad impression ... The credibility of the institution (judiciary) and its own power to execute death sentence is at stake," he said.

The Supreme Court had formed a three-member commission headed by a former apex court judge to inquire into the alleged encounter.

Police had claimed that all the four accused in the Hyderabad case were shot dead in "retaliatory" firing by the cops when two of the accused opened fire at them after snatching their weapons and tried to escape from the site where they had been taken for a reconstruction of events as part of the investigation.

Though human rights activists had questioned the police claim, a section of people had justified the killings.

The four Nirbhaya case convicts are playing with judicial machinery and trying the patience of the nation, Mehta said, adding that any delay in the execution of death penalty will have a dehumanising effect on the convicts.

While Mukesh and Vinay Sharma's mercy pleas have been rejected by the President, Pawan has not yet filed it. Akshay Singh's mercy plea was filed on Saturday and is pending.

Advocate A P Singh, who appeared for convicts Akshay Singh (31), Vinay Sharma (26) and Pawan gupta (25), opposed the Centre's plea to set aside the stay on execution of death sentence.

John raised preliminary objection on the Centre's plea saying it was not maintainable. She contended that the Centre was never a party in the case proceedings before the trial court and while the government was accusing the convict of delay, it has woken up just two days ago.

"It was the victim's parents who moved the trial court for issuance of death warrants against the convicts. At no point the central government or the state government approached the trial court to immediately issue death warrants," John argued.

John told the high court that the Centre has moved a plea in the Supreme Court seeking clarification whether co-convicts can be executed separately and this petition is pending before the apex court.

Mehta, however, said convicts are not to be hanged only till the stage of their SLP before the Supreme Court.

Seven years have gone by but the convicts are still playing with the state machinery and the judicial system, he said, adding that the crime committed by these convicts was so ghastly that it has shaken the conscience of the nation.

Opposing the plea, John urged that she was only pressing for a common execution, if at all it happens, and as on today there was no definitive order to single order the executions of the convicts.

She added that a common judgement was passed by the trial court that they be hanged by neck till death and the death row convicts have every right to avail the remedies available to them till their last breath.

John said the day is not far away when the execution will happen but nobody should circumvent the procedure as it the the question of life of a person.

She argued that the Supreme Court has never said that the convicts delayed the process and his curative petition as well as mercy petition by the President was rejected on merits and not due to delay.

A 23-year-old paramedic student, referred to as Nirbhaya, was raped and brutally assaulted on the intervening night of December 16-17, 2012 inside a moving bus in south Delhi by six persons, before being thrown out on the road.

She died on December 29, 2012 in Singapore's Mount Elizabeth Hospital.

One of the six accused in the case, Ram Singh, allegedly committed suicide in the Tihar Jail.

A juvenile, who was among the accused, was convicted by a juvenile justice board and was released from a reformation home after serving a three-year term.

The top court, in its 2017 verdict, had upheld the capital punishment awarded to the convicts by the Delhi high court and the trial court.

