The hearing in the infamous December 16 gangrape-cum-murder case in Supreme Court today saw a lawyer contending that the conviction of the accused was based on a wrong assumptions as the police had failed to show that there was a "conspiratorial relationship" among each one of them.

A three-judge bench headed by Justice Dipak Misra heard the matter on Saturday, even though it was a holiday, and recorded the submission of Amicus Curiae and senior advocate Sanjay Hegde, who was appointed to assist the apex court in the case.

"Thus, what is to be considered in this case by this court is to ascertain the 'foreseeability' with regard to the offence of murder by all the accused in the course of their alleged plan of merry-making.

"The prosecution story lacks in evidence to show that the petitioners/accused were in conspiratorial relationship with each member, which would have made them to reasonably foresee the plan of merry-making turning into an offense of murder," Hegde submitted.

A 23-year-old paramedic, named by the media as Nirbhaya, was brutally assaulted and gangraped by six persons in a moving bus in South Delhi and thrown out of the vehicle with her male friend on the night of December 16, 2012. She had died in a Singapore hospital on December 29.

Hegde said there must be a meeting of minds resulting in the ultimate decision taken by conspirators regarding the commission of offence and the prosecution has to show that the circumstances give rise to a conclusive or irresistible inference of an agreement between two or more persons.

"A few bits here and a few bits there on which the prosecution relies, cannot be held to be adequate for connecting the accused with the commission of the crime of criminal conspiracy," he argued.

The senior lawyer further said the Delhi High Court did not go into the question of whether the prosecution has discharged its burden to prove the existence of a criminal conspiracy at all.

The apex court had appointed senior advocates Hegde and Raju Ramachandran as amicus curiae to assist the court in the matter.

While Ramachandran would assist the court in the appeals of convicts Mukesh and Pawan, Hegde would assist in appeals of other two convicts, Vinay Sharma and Akshay Kumar Singh