Defense lawyers for three Bulgarians charged with complicity in the May 1981 attempt to kill Pope John Paul II asked the court today to subpoena a Neapolitan gangster who claims Italian intelligence agents convinced papal assailant Mehmet Ali Agca to implicate Bulgaria deliberately.

The request for the subpoena of Giovanni Pandico, an informer who has been testifying at a Naples trial of suspected members of the "Camorra," the Neapolitan underworld, was made by Manfredo Rossi, lawyer for Agca's Bulgarian and Turkish alleged accomplices in the attack on the pope. Pandico made the statements regarding Agca to the Italian weekly, Espresso.

The eight-member tribunal headed by Magistrate Severino Santiapichi ruled that it would consider the request later.

The bulk of today's session, the 13th since the trial opened here May 27, was dedicated to an examination of films and photographs of the pope's shooting in St. Peter's square May 13, 1981. Judge Santiapichi questioned Agca extensively about the alleged second Turkish assassin, fugitive Oral Celik.

Pandico claims that in March 1982 a top Italian intelligence officer now on trial for unauthorized intelligence activities, had offered the Camorra protection for underground leader Rafaele Cutolo in return for convincing Agca to help implicate officials from Bulgaria and the Soviet Union.

At the time, Cutolo and Pandico were imprisoned in the Ascoli Piceno jail where Agca was serving a life sentence for attempting to kill the pope.

For many months after his arrest and sentencing, Agca insisted he had acted alone in trying to murder the pope. Records show he was interviewed by two secret service officers in December 1981 and began cooperating with Investigating Magistrate Ilario Martella in May 1982.

But according to Pandico, Agca changed his mind because of promises of help in getting out of prison. Today in Naples, Pandico, whose mother was murdered in a vendetta bombing two weeks ago, added that Agca also had been promised a job as a Camorra killer.

The lawyer for the Bulgarian Airlines official charged in the case said discrepancies in Agca's testimony had led defense attorneys to believe Agca had been coached.