The apex court bench of Justice H.L. Dattu and Justice C.K. Prasad reserved the order after it was told that the delay in trial was not because of any dilatory tactics by the accused or the prosecution but on account of a systemic failure.

The court cited three other cases in which trial has been going on for over three decades and said: "Therefore, to say that that your case is unique is not justified."

Senior counsel Tehmtan R. Andhyarujina, appearing for Dwivedi, said: "The system has failed causing great violation of (accused's) right under Article 21 (right to life and liberty)" and the case was "most intolerable and graphic example of systemic failure and the same can't be excused".

"If I am responsible for the delay then I have no right to come before this court," said Dwivedi, 64, adding "if it is a systemic delay then the right of the accused has been infringed and the charges should be quashed".

"If the delay of 37 years is pardonable then what is the value of Article 21" that provides for speedy trial, said the senior counsel.

"It is not just the life of the accused but even that of his immediate family that gets haunted by such delay," he said.

As the senior counsel sought to describe the case as unique on the grounds of delay of 37 years, Justice Dattu pointed to three other cases in which the trial had not concluded even after more than three decades.

One of the cases cited by Justice Dattu related to 1959. The other two cases related to 1979 and 1983.

The court said that one of the accused in the Mishra assassination case had now sought the assistance of a counsel from legal aid cell.

The court said that now this counsel will ask for all certified copies of the case records, including that of the chargesheet. The court observed this would contribute to further delay.

Andhyarujina said that "systemic failure is not to be condoned and tolerated" and added that "in the interest of justice and humanitarian aspect of this case the trial in this case requires to be quashed".

Appearing for the Central Bureau of Investigation (CBI), Additional Solicitor General Harin Raval told the court that the principle of criminal law was that though the crime was committed against an individual but it was construed to be committed against the society, thus, the accused must face its consequences.

"It is not the delay alone which is the load factor for quashing the proceedings," Raval said.

He contended that the nature of the offence was equally relevant and the "real purpose is to find out the truth and the same can be done by concluding the trial".

Raval assured the court that the CBI would not seek any unnecessary adjournments.

The case relates to the throwing of a bomb at the dais where the then railway minister was addressing a public meeting in Samastipur in Bihar Jan 2, 1975. Mishra, injured in the attack, succumbed to injuries in hospital the next day.

Dwivedi is one of the accused who threw a bomb at the dais when Mishra was addressing the meeting.

The trial started in Bihar but was later shifted to Delhi.