Why does America's largest labor union keep getting its presidents indicted, but then keep reelecting them anyway? What is the secret of the International Brotherhood of Teamsters?

To answer this, picture yourself on the arena floor at the Las Vegas Convention Center last Wednesday as a local Teamster official from say, St. Louis. You are about to cast your vote for president.

You have spent 29 years as a Teamster, and most of the time, you wear the Teamster pin on your lapel with pride. Since you became a union officer nine years ago, you've moved up to $45,000 a year plus expenses, and you drive a union car. Pretty good for a guy who started out making just over minimum wage, working nonunion construction. When you joined the Teamsters in '57, you finally started making real dough, especially after you got elected an officer.

But sometimes you are sick of taking all this abuse. Your neighbors joke about the Mafia. They ask whether you have left any bodies in trunks lately, and when you put in the new pool last month, one of them joked that you must have just taken another payoff. Your daughter asks whether all the bad things she heard on TV about your union are really true.

Just before you left for Vegas, your wife asked you what you thought of Jackie Presser. Were you really going to vote for him as president of the union? After all, he had just been indicted. The newspapers said he was an FBI informant and was also in with the mob; and besides that, she asked, why in the world does this big lug Presser get paid $550,000 a year, plus expenses, while the guys in Local 688 are making $14.31 an hour driving these huge rigs on long hauls away from home?

The thoughts of this hypothetical Teamster are the product of interviews last week with more than 25 local union officials

Most were hostile and distrustful of reporters because they believe that labor unions -- theirs in particular -- have been unfairly portrayed in the media, and many don't want their names to appear in news stories.

The Teamsters, with more than 1.6-million members "the largest union in the free world," is a world unto itself, a sometimes frightening enigma to those who study it. Its very success as a union made it an attractive target for organized crime, lured by massive union pension funds and by the centralized power of a union that at times could be twisted into a base for extortion and racketeering, occasionally even murder.

The other side of the story, which union officials insist is rarely told, is the role of 700 different Teamsters locals around the nation in bettering the lives of their members: winning the best contracts in various industries, strongly supporting progressive legislation, vigorously backing community programs and charities, and, in a bleak era for unions, building a modern, fully computerized Washington headquarters whose research, legal, lobbying, communications and organizational capabilities dwarf those of most other unions in America.

Presser is the fourth Teamster president of the last five to be indicted, and the third elected while facing criminal charges. The outside world wonders when the Teamsters will ever clean house.

But inside the union, it is seen differently: the Teamsters are persecuted, investigated more than anyone else, often wrongly accused, and the actual crimes of a few are exaggerated to discredit the union -- because government and corporate officials don't like strong unions.

The people who actually vote at the Las Vegas convention are not the membership. Most are elected officers who automatically become convention delegates, a process that critics charge gives unfair advantage to incumbent presidents, because there is rarely any pre-convention campaigning for delegates, during which insurgents might mount a challenge.

Not surprisingly, when the Teamster tally was over, Jackie Presser had 98.5 percent of the votes cast, and moralists in the media once more shook their heads.

But look at it from inside the head of a hypothetical Teamster as he lined up at the microphone among 1,900 fellow Teamster delegates to cast his vote:

He realizes that you have to wonder sometimes about all this mob stuff, and the union's bad image, and you don't have all the answers. The easiest answer is how to vote: Presser. Nobody is running against him anyway, except some local guy from Cleveland nobody ever heard of.

The real power in this union is in the Big Brass -- the two top officers and the 16 vice-presidents. These guys come up with a candidate for president -- who knows how they do it -- and we then just give it the okay.

You don't really believe Presser is guilty of embezzling Teamster funds. Some guys in the local think he's a crook, but most believe he's innocent and will get acquitted.

But more important than that, Jackie hasn't raised union dues. Guys already complain about $28 a month, but they're at least glad that Presser hasn't raised dues since he's been in. Nothing like keeping taxes down to help a politician. So the men said you should vote for Jackie, as if there was any other choice.

You remember how they were always trying to pin something on Hoffa too. Ah, Jimmy Hoffa. You remember meeting him at the 1966 convention in Miami Beach. What a guy. He was the toughest and smartest ever. He had some bad associates, the mobsters who eventually killed him in '75.

But Jimmy Hoffa only got involved with the mob because all those trucking companies were hiring goons to beat up the men to stop the union, right? Hoffa knew the Detroit gangs that could help them fight back. He was always out to help the men. Hoffa even remembered your name two years after you met him.

Presser seems to be doing a pretty good job, you figure, at least compared to the last two guys, Frank Fitzsimmons and Roy Lee Williams. You've only had to call the union headquarters in Washington a few times in the last year, but Jackie's people were really helpful and they knew what they were doing. They gave you some help on contract language and you got that $12,000-a-month grant to help expand the local by organizing some city workers who wanted to join.

Guys joke sometimes that if you vote against Jackie you'd get your legs broken. You know that's not true. But you wonder if you ever decided to vote against Jackie . . . you wonder if you'd get as much help -- or any help -- the next time you call Washington.

You remember reading about Roy Williams, before he went to prison for trying to bribe some senator from Nevada. You remember him testifying that he took orders from the Kansas City mob, and he said Presser was owned by the Cleveland mob. Maybe it's true, but you doubt it. They're always saying bad things about the Teamsters.

But you do know for sure about the "dirty" locals, the New York and Chicago wise-guys. You've never actually met these people, but you know most of the stories are true. The broken legs and the guys in Cleveland blown up in the union parking lot. You remember the Central States Pension Fund troubles, the scandals when some of the old-timers' retirement money instead went into loans to the Vegas casinos, to make more money for the mob. That was sleazy stuff.

But since the Labor Department stepped in a few years ago, you know the fund is mostly clean now, no more shady Vegas loans. You are also proud of your own local union. You're doing the best you can, considering that a lot of unions are going down the tube lately. You know this local is clean. You did get offered a payoff once, during a strike, from a trucking exec who asked you to "take care of the problems." But you told him to stuff it. You feel like you've done pretty well for your members and yourself. If you can stick it out past 10 years as a union officer, you'll get the second pension from the international union. So why make waves?

You make a note to tell your wife about the Teamster videos at the convention, the video of Vice once more shook their heads.

But look at it from inside the head of a hypothetical Teamster as he lined up at the microphone among 1,900 fellow Teamster delegates to cast his vote:

He realizes that you have to wonder sometimes about all this mob stuff, and the union's bad image, and you don't have all the answers. The easiest answer is how to vote: Presser. Nobody is running against him anyway, except some local guy from Cleveland nobody ever heard of.

The real power in this union is in the Big Brass -- the two top officers and the 16 vice-presidents. These guys come up with a candidate for president -- who knows how they do it -- and we then just give it the okay.

You don't really believe Presser is guilty of embezzling Teamster funds. Some guys in the local think he's a crook, but most believe he's innocent and will get acquitted.

But more important than that, Jackie hasn't raised union dues. Guys already complain about $28 a month, but they're at least glad that Presser hasn't raised dues since he's been in. Nothing like keeping taxes down to help a politician. So the men said you should vote for Jackie, as if there was any other choice.

You remember how they were always trying to pin something on Hoffa too. Ah, Jimmy Hoffa. You remember meeting him at the 1966 convention in Miami Beach. What a guy. He was the toughest and smartest ever. He had some bad associates, the mobsters who eventually killed him in '75.

But Jimmy Hoffa only got involved with the mob because all those trucking companies were hiring goons to beat up the men to stop the union, right? Hoffa knew the Detroit gangs that could help them fight back. He was always out to help the men. Hoffa even remembered your name two years after you met him.

Presser seems to be doing a pretty good job, you figure, at least compared to the last two guys, Frank Fitzsimmons and Roy Lee Williams. You've only had to call the union headquarters in Washington a few times in the last year, but Jackie's people were really helpful and they knew what they were doing. They gave you some help on contract language and you got that $12,000-a-month grant to help expand the local by organizing some city workers who wanted to join.

Guys joke sometimes that if you vote against Jackie you'd get your legs broken. You know that's not true. But you wonder if you ever decided to vote against Jackie . . . you wonder if you'd get as much help -- or any help -- the next time you call Washington.

You remember reading about Roy Williams, before he went to prison for trying to bribe some senator from Nevada. You remember him testifying that he took orders from the Kansas City mob, and he said Presser was owned by the Cleveland mob. Maybe it's true, but you doubt it. They're always saying bad things about the Teamsters.

But you do know for sure about the "dirty" locals, the New York and Chicago wise-guys. You've never actually met these people, but you know most of the stories are true. The broken legs and the guys in Cleveland blown up in the union parking lot. You remember the Central States Pension Fund troubles, the scandals when some of the old-timers' retirement money instead went into loans to the Vegas casinos, to make more money for the mob. That was sleazy stuff.

But since the Labor Department stepped in a few years ago, you know the fund is mostly clean now, no more shady Vegas loans. You are also proud of your own local union. You're doing the best you can, considering that a lot of unions are going down the tube lately. You know this local is clean. You did get offered a payoff once, during a strike, from a trucking exec who asked you to "take care of the problems." But you told him to stuff it. You feel like you've done pretty well for your members and yourself. If you can stick it out past 10 years as a union officer, you'll get the second pension from the international union. So why make waves?

You make a note to tell your wife about the Teamster videos at the convention, the video of Vice President Bush, the "Proud to Be a Teamster" song, and even the $35 quartz wristwatch with Jackie's picture on it. Jackie's got class. He even hired this fancy Washington PR firm, Gray & Co. for all this slick stuff, which truckdrivers like Fitz and Williams would never have even thought of.

A strange thing happened at the Teamsters convention last Tuesday in Las Vegas. The Teamsters leadership introduced a constitutional amendment that would have stripped Jimmy Hoffa of his title of "General President Emeritus for Life." Hoffa got the president-for-life title in 1971, while in prison on his jury-tampering conviction. Now, they said, 11 years after his disappearance, the title was no longer applicable.

But for the first and only time at the convention, the membership revolted. Delegates from Hoffa's hometown Detroit rose to oppose lifting his title. Hoffa was a great man, they said, and besides, one delegate said, "The man is not here, but it hasn't been proven that he may not be back." You're glad they didn't take Jimmy Hoffa's title away. You look up at Jackie banging his gavel on the podium. He's definitely the best president since Hoffa. You're damn tired of hearing these people who don't even know Jackie, and who never knew Jimmy, calling them crooks . . . "I vote for Jackie Presser," you say proudly.

That big party at Caesars Palace was incredible last night. You remind yourself to tell your wife about how these guys dressed in Roman togas carried in Jackie, all 300 pounds of him, on this big chariot thing. These guys really know how to throw a party.