Seven years ago today, Jimmy Hoffa disappeared, leaving virtually no trail. The body of the tough Teamster leader has never been found, and investigators expect no immediate break in the case.

Under Michigan law, James R. Hoffa can now be declared legally dead, and his son, James P. Hoffa, is in the process of filing the necessary papers, hopeful that the remaining Hoffa family can close that chapter of their lives and begin the three-year process of settling Hoffa's estate.

There are many theories about what happened to Hoffa: that he was buried--in a Michigan cornfield, in a New Jersey dump, or under countless construction projects--or that he was ground up and put in a Florida swamp.

The most popular theory, however, is that he was compacted, shredded and incinerated at a garbage disposal company in Hamtramck, just outside Detroit. No one seems to believe Hoffa is still alive.

But his legend dominates the Teamsters, even today. William E. Bufalino, a 35-year Teamster who was Hoffa's lawyer for 25 years, said sadly, "There'll never be another one like that in the Teamsters. If he was a woman, he'd be pregnant every nine months. He didn't know how to say no. He did so many favors for so many people."

Local 299--where Hoffa started with the Teamsters--looks much as he left it, a complex of low, brick buildings in a run-down, rubble-strewn neighborhood behind Tiger Stadium. Outside, black Lincolns, Cadillacs, Oldsmobiles and Mercurys line the curbs.

The strange story of Hoffa's disappearance began at a modest, two-story home in the town of Lake Orion about an hour north of Detroit. Today, the house with white aluminum siding is quiet and empty.

On July 30, 1975, Hoffa left the house alone around 1:15 p.m., telling his wife Josephine that he was meeting some men for lunch and would be home by 4 p.m.

As the story was later pieced together, Hoffa stopped by a friend's office and named the men he planned to meet. Later, under hypnosis, workers there told investigators that Hoffa named Anthony (Tony Jack) Giacalone, a reputed figure in the Detroit Mafia, and Anthony (Tony Pro) Provenzano, reputed as a captain in the Vito Genovese organized crime family in New York and New Jersey.

Provenzano and Hoffa had feuded while both were in Lewisburg prison. Hoffa was there from 1967 to 1971 on a jury-tampering conviction, but continued to run the Teamsters until 1971, when the late Frank Fitzsimmons became president.

Hoffa was paroled by President Nixon later in 1971 on the condition that he not hold union office until 1980. Hoffa filed suit to have the stipulation overturned, and made it clear that he planned to resume the leadership of the Teamsters. He reportedly believed Fitzsimmons double-crossed him by persuading Nixon to grant the conditional parole.

Fitzsimmons, meanwhile, liked the limousines, the union-provided homes and the unlimited expense account. It was clear that he would not give up without a struggle.

Bufalino said, "Jimmy wore white cotton socks. When he became president, he bought a Pontiac convertible, and he drove himself around, none of these chauffeured limousines you see today."

Bufalino complains that when Fitzsimmons took over the Teamsters, he "took up golf."

After Hoffa disappeared, investigators were told that Hoffa was considering blowing the whistle on some shady Fitzsimmons deals to enhance his own reelection effort, but some time later an underworld informer testified at a Senate hearing that Hoffa had planned to have Fitzsimmons and Provenzano murdered, that they heard about the plot and that they simply got him first. Officials don't know the actual motive for Hoffa's disappearance or who is responsible. And no indictments have ever been handed down.

Hoffa apparently asked his old friend Giacalone to set up the lunch with Provenzano for peace talks aimed at bringing Provenzano into line behind Hoffa.

The lunch was to have occurred at the Machus Red Fox Restaurant in a suburb north of Detroit. A busy restaurant with prices appealing to an expense-account clientele, the Red Fox is located on a four-lane highway beside a shopping center.

Two witnesses later told police that they had seen Hoffa standing in the parking lot, clearly waiting for someone. Around 2:30 p.m., Hoffa called his wife to ask if Giacalone had called. Then he called a friend to tell him Giacalone and Provenzano had failed to keep the date.

That was the last anyone ever heard from Jimmy Hoffa. The next morning, his 1974 Pontiac was found in the Red Fox parking lot, with no signs of a struggle.

Investigators first talked about three possible scenarios: Hoffa was kidnaped for a ransom, he voluntarily disappeared or he was executed. As time passed, most agreed that Hoffa was probably dead.

Giacalone and Provenzano established alibis and said they knew nothing about a lunch meeting.

Investigators found two witnesses who claimed to have seen a man resembling Hoffa in the back seat of a maroon car about that time.

They reportedly told investigators that the driver looked like Charles L. (Chuckie) O'Brien, a union employe regarded as a foster son to Hoffa. O'Brien never lived with Hoffa, but the families were close. In an autobiography in progress when he disappeared, Hoffa said he helped with O'Brien's education and treated him as a son after O'Brien's father died.

O'Brien was driving a maroon Mercury that day which he had borrowed from Giacalone's son Joey. When the FBI impounded the car, blood stains were found on the seat.

O'Brien reportedly first told investigators that he had spent that afternoon at an athletic club with the elder Giacalone. After the club did not back his alibi, O'Brien said he was delivering a 20-pound salmon to a local union official, according to newspaper accounts. He reportedly said the fish was responsible for the blood on the front seat.

The FBI conducted an exhaustive search of the car. In fact, it is believed the FBI still has the car in a garage somewhere in Detroit. It was reported at the time that specially trained search dogs found Hoffa's scent in the back seat and the trunk.

When Bob Reutter, assistant special agent in charge of the Detroit FBI office, was asked about the car this week, he smiled and said, "Everything about that car is off limits."

Even now, Reutter will not give a personal theory on Hoffa's disappearance, but he believes he knows who was involved and generally what happened to the body.

Reutter said he believes the case provides an "interesting parallel" to that of Anthony Castellito, a New York Teamsters official who was kidnaped and murdered in 1961. His body was never recovered. In 1976, the FBI solved the case. Provenzano is serving a life sentence for ordering Castellito's murder.

Provenzano had an alibi the day of the Castellito murder. Reutter said, "Provenzano was marrying his second wife when Castellito disappeared."

Much of the grand jury questioning in the Hoffa investigation was said to be focused on O'Brien, Provenzano and Giacalone, along with a group of four New Jersey men with reputed connections to the Teamsters and organized crime. They included Thomas and Stephen Andretta and Gabriel and Salvatore (Sally Bugs) Briguglio.

Sal Briguglio, a Mafia hit man and business agent for Provenzano's local Teamsters union, was also indicted in the Castellito murder but died in a gangland-style execution in 1978 before he could be tried. During recent Senate hearings concerning Labor Secretary Raymond J. Donovan, Briguglio was mentioned as an alleged Donovan associate. Donovan denied knowing Briguglio.

The Andrettas and Briguglios said they were in New Jersey playing cards when Hoffa disappeared.

The four brothers and Provenzano were all represented in the grand jury investigation by Bufalino, 64, and in semiretirement after a stroke, two heart attacks and leukemia. He said recently that they were not involved in Hoffa's disappearance.

"If I knew, I would tell. I would have quit right then and there if I thought they had anything to do with it or if I thought they had guilty knowledge," Bufalino said.

Bufalino, whose office walls are covered with pictures of himself with Hoffa over the years at courthouses and congressional committees, said he believes the FBI or the CIA might have had something to do with the disappearance.

Reutter is convinced that the case will be solved, no matter how long it takes. He's still waiting for a break, for one crucial person to come forward. Until someone does, the FBI is likely to be applying as much pressure as it legally can on those people believed to be involved.

Hoffa's son said, "It's been a terrible ordeal, a long, seven-year period of uncertainty." But despite the personal loss, the innuendo about mob connections and the years of media attention, he said he's glad to share his father's name. "The name has been a blessing. I'm very proud of my name."