Jimmy Hoffa riddle continues 49 years later; FBI file connects Teamsters boss to Chicago mob

CHICAGO (WLS) -- It was 49 years ago this week that the former Teamsters union leader, Jimmy Hoffa, vanished without a trace, and the Hoffa riddle is a befitting title for the anniversary week of his disappearance.

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James R. Hoffa's middle name was Riddle, and the case remains that for the FBI and it's one of America's most enduring crime questions: What Happened to Jimmy Hoffa?

Hoffa was last seen July 30, 1975 outside a swanky restaurant near Detroit for a lunch date with two known gangsters that never happened.

Hoffa's last call was made from a pay phone to his wife to say he'd been stiffed.

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For years authorities followed leads in fields on horse farms; under a backyard swimming pool; beneath a home garage; at a New Jersey dump-site and in the concrete of an NFL stadium, but nothing came of the searches.

Mobologists continue to zero in on Hoffa's ties to the Chicago Outfit that had infested the Teamsters Union Central State's Pension Fund worth millions, which helped bankroll early Las Vegas.

"The growth of Las Vegas in the 1950s and 60s in particular, was fueled largely by the Teamsters Pension Fund, and by Jimmy Hoffa, I mean, I felt was a huge figure in Las Vegas at that time. It was funded in the mid 60s, almost entirely by Teamsters money. And so Jimmy Hoffa was treated like royalty," explained Geoff Schumacher, Vice President of Exhibits and Programs at the Mob Museum in Las Vegas.

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It was a different story after Hoffa did prison time for fraud and jury tampering and then tried to muscle back into the union.

The official FBI "Hoffex" file concludes that he "was killed because of his attempts to re-enter Teamster Union politics."

The FBI has focused on New Jersey hoodlum Anthony "Tony Pro" Provenzano and Detroit mafia chief Anthony "Tony Jack" Giacalone, both of whom Hoffa was to meet at that restaurant 49 years ago this week.

Authorities have indicated it was a likelihood that Chicago outfit bosses signed off on the gangland hit.

"It could very well be that the outfit endorsed it, promoted, wanted it to happen, but wanted to keep its fingers off, too, right because they would be immediately suspect. So as soon as you you know, and it was a outfit at that time was one of the most investigated organized crime groups in America, right, said Schumacher, "The fact that they perhaps were not Chicago hit-man that maybe it was a combination of New Jersey and you know, and Detroit figures made it a little harder to solve the case."

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Schumacher tells the I-Team that Jimmy Hoffa tried to big-foot Chicago mob bosses and that Hoffa's replacement Frank Fitzsimmons was always more of a patsy for the Outfit. He suggests that may also have been a motivation for the mob to eliminate Hoffa.

Most investigators to this day believe Hoffa's body has never been found because it was quickly dissolved in a chemical vat at a Detroit factory.