The arguments were made by Kasab's lawyer Amin Solkar before justices Ranjana Desai and R V More of the Bombay High Court, who are hearing the confirmation of the death sentence awarded to him by the trial court for his role in the 26/11 terror attacks.
The defence lawyer argued that there was no material to suggest that Kasab was part of the conspiracy relating to attacks on Hotel Taj Mahal, Hotel Oberoi-Trident and Nariman House. His role was confined only to attacks at Chhatrapati Shivaji Railway Terminus and in and around Cama Hospital.
"At the most, it can be said that Kasab had performed the role of a contract killer and could be held responsible for the death of persons at CST and the surrounding areas," Solkar argued.
The basic thrust of arguments by the defence lawyer was to minimise the role of Kasab in the conspiracy and aim at commuting his death sentence to life imprisonment.
Kasab had no role to play in the attacks on hotels Taj Mahal, Oberoi and Nariman House and there is no evidence to this effect, Solkar submitted.
Kasab did not appear on Monday on the screen put up in the court for the videoconference link to enable him to hear arguments from jail.
Solkar said when an accused makes a confession it could result in conviction. Similarly, when a guilt plea is made before the court it should be considered like confession.
In this case, Kasab has made a confession as well as guilt plea. Both these confessions were contradictory to each other and should not be accepted because they create doubts as to which one should be believed, he argued.
Pointing out the contradictions in confession and guilt plea of Kasab, Solkar said Kasab had admitted before a magistrate that he had killed Amarsingh Solanki, navigator of the fishing trawler Kuber through which terrorists arrived in Mumbai by sea route. He also admitted to have killed police officer Tukaram Ombale in an encounter at Chowpatty.
However, in the guilty plea, Kasab denied having killed Solanki and Ombale. He had told the trial court that he was not aware who killed Solanki and that he had seen slain terrorist Shoaib coming out of boat's cabin with a knife smeared with blood and throwing it in the sea.
In the guilty plea, Kasab had also said that outside Cama Hospital, he and Abu Ismail were under attack from police officers in a jeep and that before he could retaliate the policemen fired at him because of which he sustained injury in hand. He also blamed Ismail for killing officers Hemant Karkare, Vijay Salaskar and Ashok Kamte.
In the guilt plea, Kasab said that at Girgaum Chowpatty, constable Tukaram Ombale had caught hold of his collar and pulled him out of the car in which he was seated with Ismail. He further said he was surrounded by policemen who assaulted him and he fell unconscious. When he gained consciousness he was in hospital.
However, in confession before a magistrate Kasab had admitted to have killed Ombale.
Denying role of Kasab in the conspiracy, his lawyer said at the most it can be said Kasab had executed the conspiracy and that he could be charged for murders like any other contract killer.
To substantiate his argument, Kasab's lawyer Solkar referred to Supreme Court judgment in Rajiv Gandhi assassination case in which Nalini was an accused.
Solkar said in Nalini's case, the Supreme Court had laid down four categories of conspiracy -- core planning, aiding and abetting, being part of conspiracy and executing it and lastly executing the conspiracy. Kasab fell in the fourth category, he argued.
To establish a conspiracy there has to be meeting of minds and there is nothing to suggest this aspect in Kasab's confession, he argued. The only material relied upon by the prosecution was Kasab's confession before a magistrate which he retracted later and also contradicted it in his guilty plea.
The court is currently hearing confirmation of death penalty given to Kasab for his role in dastardly attacks.Kasab's appeal against his conviction is yet to come up for hearing while government would argue later on its appeal against acquittal of co-conspirators Faheem Ansari and Sabauddin Ahmed.