James Caan on the Witness Stand : Trial: The actor, who played a mobster’s son in ‘The Godfather,’ will be a character witness for an alleged crime figure.

James Caan, the actor who first gained fame as a mob kingpin’s son in the classic film “The Godfather,” has a new role in real life: Character witness for an alleged organized crime leader accused of cocaine trafficking and a string of robberies and kidnapings.

Caan calls Ronald A. Lorenzo “my best friend.” Prosecutors in Los Angeles hold another view of the 46-year-old businessman: They allege that Lorenzo is a capo of the New York-based Bonanno crime family, a drug merchant and a ringleader of robberies and kidnapings of affluent San Fernando Valley residents.

Opening arguments in the first of three cases against Lorenzo are to begin today in U.S. District Court. If convicted of all charges facing him, Lorenzo, who has been incarcerated at Los Angeles County jail since June on bail of $2 million, faces life in prison without the possibility of parole.

Caan has emerged as Lorenzo’s most committed backer.

Court records show that on June 10 Caan pledged his Bel-Air home as collateral for Lorenzo’s bail of $500,000 on the federal drug charges. Lorenzo was arrested the next day on separate local charges related to robbery and kidnaping. Last month, Caan testified in Los Angeles Superior Court that he “made sure that Ronnie had proper (legal) representation” and would like to pledge the same Bel-Air home to help Lorenzo meet the separate, $2-million bail.

And--to guarantee he can appear this week in federal court as a witness for Lorenzo--Caan has postponed at “great personal expense” the start of filming in Dallas of his newest movie, “Flesh & Bone,” an independent production to be distributed by Paramount Pictures, according to a lawyer for Lorenzo.

Caan says he has spent time with Lorenzo “just about every day” for the last five years, and that Lorenzo is the manager-in-waiting of a pizzeria the actor just opened in Beverly Hills.

“He is my best friend and I love ‘em,” Caan said in a statement read to The Times by his agent. “That’s the way I was raised and I know of no other way. I know of no crime this man has committed. And had he, he wouldn’t be my best friend.”

Caan, 52, gave a similar account in 1985, when he appeared in New York at a much-publicized trial to show his support for two other men with alleged mob ties, kissing one of the defendants, Carmine Persico, on the cheek.

Caan, raised in the borough of Queens, later told the Chicago Tribune: “I would never deny that my friend is my friend. Where’s the morality in that?”

In Los Angeles, Lorenzo’s lawyers, Gerald V. Scotti and Kevin B. McDermott, say they will argue that their client was entrapped in the federal drug case and has been charged on the basis of flimsy evidence in the separate robbery-kidnaping indictment. As for the assertions in court by Deputy Dist. Atty. John Monaghan and others that Lorenzo is a member of organized crime, McDermott said:

“He grew up in Hell’s Kitchen (in New York City), best friends with people you and I probably wouldn’t associate with. But he’s got no convictions in his background.” Still, McDermott said that Lorenzo’s $2-million bail--higher than that imposed on some murder defendants--is directly attributable to prosecutors’ allegations that he is a member of the Bonanno crime family.

“It always impresses everybody,” McDermott said, “. . . when you can make an allegation that somebody is a capo .”

McDermott said Lorenzo denies he is part of organized crime--but that he moved from New York to the Los Angeles area in 1982 “to start fresh,” concluding, “If you lay down with dogs, you get fleas.”

Caan, in his testimony last month before Superior Court Judge Nancy Brown, said he met Lorenzo about 15 years ago during filming of the movie “Chapter Two.” Asked by county prosecutor Monoghan, “How did you come about meeting him while you were filming?” Caan replied:

“Through a couple of other friends. You know, I’m from New York. Some homeboys.”

Caan also testified that from 1987 until Lorenzo’s arrest in June, 1992, he spent time with him “just about every day. . . . I certainly don’t condone crime, but if this man committed a crime, he would have to be Houdini. I’m with him all the time.”

Yet the charges pending against Lorenzo allege that he was involved in a flurry of criminal activity from 1988 through 1990:

A county grand jury in April indicted Lorenzo on charges that he committed four crimes related to the San Fernando Valley robberies and kidnapings in 1988, 1989 and 1990, according to court records and McDermott, one of Lorenzo’s lawyers.

The District Attorney’s office has succeeded in keeping the indictment of Lorenzo and two other men sealed--even though all three defendants have long since been in custody and are scheduled to go to trial late this fall. Monoghan, the prosecutor who requested the secrecy--a tactic described by other attorneys as highly unusual--did not return phone calls from The Times.

According to McDermott, the “Valley crimes” Lorenzo is alleged to have helped plot included the robbery of a prominent film director and TV producer and the hogtying, kidnaping and extortion of a major Los Angeles bookmaker. Names of the victims have not been revealed publicly. Caan, in his testimony last month, said that he has frequently ridden a motorcycle with one of Lorenzo’s co-defendants in the case, and has known the third defendant for “six, seven years.”

The county indictment of Lorenzo, McDermott said, alleges “that he was a ringleader . . . the one getting all the inside information” regarding potential robbery targets. McDermott said the indictment also accuses Lorenzo of “gathering up the (stolen) goods and getting it fenced.” Lorenzo has pleaded not guilty to the charges; McDermott said the case relies heavily on a paid informant who also is important to the federal prosecution.

The six-count federal indictment of Lorenzo alleges that, during 1989 and 1990, he helped organize and participated in the buying and selling of roughly six kilograms of cocaine at various restaurants and markets in Hollywood, Woodland Hills and Santa Monica.

“We’re not denying that Mr. Lorenzo engaged in part” of the activities described in the indictment, said attorney Scotti--adding that he will call Caan today as his first witness. Scotti contended that Lorenzo, because of financial difficulties, fell prey to the government’s “entrapment.” Assistant U.S. Atty. Brad M. Sonnenberg declined to comment.

Caan, in his testimony last month in Los Angeles Superior Court, said that he has invested about $50,000 in the new eatery on Canon Drive in Beverly Hills, called Mulberry Street Pizzeria. Caan said in court that Lorenzo has “an obligation” to manage the restaurant, if or when he leaves jail.

It was five years ago, as the manager of another restaurant, that Lorenzo first gained notoriety in Los Angeles. Believing him to be part of a larger fraud case, Los Angeles Police Chief Daryl F. Gates alleged at a news conference in July, 1987, that Lorenzo was a “suspected organized-crime figure.” Gates further alleged that Lorenzo and others had used the Malibu restaurant he operated, Splash, for “laundering large organized-crime profits from narcotics trafficking.”

Lorenzo denied any wrongdoing at the time and was not charged in the case, which culminated with the securities-fraud convictions of founders of the Woodland Hills firm, ZZZZ Best. Splash was stripped of its state-issued liquor license after a judge ruled that the establishment was not owned by Lorenzo, as he had claimed.

As for Caan, who achieved stardom as Sonny Corleone in the “The Godfather,” his acting career has fallen and soared anew since he met Lorenzo some 15 years ago. Caan virtually retired from 1982 to 1986, accepting no roles and telling interviewers later that he overcame a cocaine “problem” after getting “professional help.” In 1989, a lawyer for Caan said the actor was “stunned and amazed” at federal affidavits unsealed in New York, alleging that members of the Genovese crime family tried to anoint Caan as the actor to play Meyer Lansky, the deceased mob mastermind, in a film about his life.

More recently, Caan has rebounded as an actor, drawing praise from critics for his performances in the commercially popular films “Misery” and “Honeymoon in Vegas.”

In his Superior Court testimony last month, Caan said he was well familiar with all the charges pending against Lorenzo. After reading the 16-page federal indictment in a room provided for him by U.S. District Judge Dickran Tevrizian, Caan said, “I found it quite odd that a man would be arrested under these nebulous charges.”