Joe Bonanno has always prided himself on being "a man of respect." At 26, he became the youngest boss the Mafia ever had. He had some narrow escapes, including a harrowing gangland kidnaping ordered by a jealous cousin.

But he survived. And he wrote a book, an autobiography called "A Man of Honor" about the "Tradition" that Bonanno brought with him from Sicily and its transformation in America.

The book never made the best-seller list but it got rave reviews in the offices of U.S. Attorney Rudolph Giuliani. Giuliani wound up his reading last spring with an indictment of some principals in the book -- the reputed bosses and high-ranking deputies who make up the so-called "Commission" that runs the Mafia.

Now, in a bizarre twist, Bonanno will get the hearing of his life, next week in a Tucson hospital, with some of the Mafia's biggest bosses expected to attend, hanging on every word.

At 81, the retired "man of respect" is being forced to give a deposition about the existence of the Commission, its activities and its members since Bonanno has said he joined it in 1931.

Anthony (Fat Tony) Salerno, alleged chief of the Genovese family, will be there, sources say. Others expected include Phillip (Rusty) Rastelli, Bonanno's reputed successor, and Paul (Mr. Paul) Castellano, whom authorities list as head of the Gambino family.

And all 13 of the defendants for a trial of the families this fall are expected to have a lawyer in attendance even though Salerno's chief attorney, Roy Cohn, is not keen about going and says he may send an assistant.

"Bonanno will be asked, 'Do you know Anthony Salerno as the boss of the Genovese family?' and Bonanno will answer 'No,' " Cohn predicted in a telephone interview.

"Then," Cohn said, "the prosecutor will ask Bonanno, 'Do you know Anthony Salerno to be a member of the Commission?' and Bonanno will answer, 'No.' That's all there's going to be to it as far as my client is concerned."

Bonanno, the only Commission member to attest to its existence, has always insisted that it was supposed to be only an advisory council or "forum" over the heads of the member families.

"As the Father of a Family, I was like a head of state," he wrote in his 1983 book. "I did the same sort of things that heads of state do on an international level. I too had to maintain internal order. I too had to conduct foreign affairs with other Families."

Over the years, however, the "conservatives" like Bonanno, the ones "steadfastly opposed to such immoral enterprises as prostitution and narcotics trafficking," came to be outnumbered. "Little by little," he wrote, "our Tradition deteriorated until it lost its connotation of honor and became instead a byword for gangsterism."

As a result, Bonanno has been ordered by U.S. District Court Judge Richard Owen to testify "in a hospital setting" in light of his failing health. At first he refused, but he has been given "use immunity" and faces jail for contempt if he does not respond.

The defendants, indicted as members and high-ranking associates of an alleged "Racketeeer Influenced and Corrupt Organization," that is, the Commission, have an interest in helping their attorneys ask the right questions. The sessions, set for Tuesday and Wednesday at St. Mary's Hospital in Tucson, will be videotaped for possible use at the trial.