As a young federal prosecutor in Manhattan, Morris Weinberg spent years investigating the allegedly criminal exploits of oil trader Marc Rich's corporate empire, securing guilty pleas and a $200 million settlement from two of his companies in 1984.

But the assistant United States attorney wasn't satisfied. He wanted jail time for Mr. Rich and Pincus Green, co-defendants in a hard-fought 65-count racketeering indictment accusing them of tax evasion, oil profiteering and unlawfully trading with Iran during the hostage crisis. At the time, the pair was living in Switzerland to avoid prosecution, so Mr. Weinberg told a reporter that he took solace in this:  They can never come back to the United States as free men.

Today, Messrs. Rich and Green, both 66 years old, can return to America unfettered, their pasts forever cleansed of criminal allegations by a pardon issued by Bill Clinton on his last day as president.

“It's astonishing,” Mr. Weinberg says now. “I don't believe people should be able to ... commit one of the biggest tax frauds in the history of the United States and just be able to walk away from it because the president pardons them in a way that completely circumvents the normal pardon process.”

Like most of the Marc Rich story, the tale of his presidential absolution remains shrouded in intrigue.  It will go down as an extraordinary feat in the annals of Washington lobbying, illustrating in dramatic fashion how money begets access, access begets influence and influence begets results.

The pardons were orchestrated by Jack Quinn, a former White House counsel who is one of the former president's closest confidants. Mr. Quinn says Mr. Rich paid his former firm about $300,000 for his and other lawyers' work on the case. He sealed the bargain in a half-hour dinnertime telephone chat with his old boss on his last night in power. The Quinn case in brief, detailed by a 3-inch-thick pardon application: These two men were wrongly indicted; overzealous prosecutors won't listen to reason; and a pardon is our last hope for justice.

The stealthy campaign to win the pardons was lubricated by $220 million worth of philanthropy from his fugitive clients that produced support from prominent citizens across the globe, including influential
constituents of the former first lady, Sen. Hillary Rodham Clinton of New York. Israeli Prime Minister Ehud Barak, grateful for Mr. Rich's financial support of peace efforts, personally lobbied the president to pardon Mr. Rich.

Mr. Quinn's efforts also were bolstered by repeated personal entreaties to the president from an unlikely advocate: Mr. Rich's former wife.

In past media interviews, Denise Rich had accused her billionaire husband of cheating and snubbing her songwriting career. She left him in Switzerland in 1993 and fought over millions in a tumultuous divorce that took years to hash out. After returning to the United States eight years ago, Ms. Rich started doling out political cash and ingratiating herself to Washington's new Democratic power-elite, headed by Bill and Hillary Clinton.

In all, she donated more than $1 million to the president's party and its campaigns, including Mrs. Clinton's Senate race, and raised untold sums more, once hosting a $3 million luncheon at her Fifth Avenue penthouse apartment in New York in 1998. “It means more now than ever, and we'll never forget it,” Mr. Clinton said at that event, three days after the release of Kenneth Starr's report on the Monica Lewinsky affair.

Ms. Rich also gave the couple a $7,375 set of two end tables and two chairs for their new house in Chappaqua, N.Y., as well as a saxophone for the president. By the time the Clintons left the White House, Ms. Rich had become a close-enough friend that she was able to lobby the president on three occasions — once in person, once on the phone and once in a letter.

More controversial than any since Gerald Ford bestowed official forgiveness on Richard Nixon or than any of the other 138 President Clinton issued Jan. 20, the Rich and Green pardons have kindled a serious debate about whether the president's constitutional and unilateral authority should be curtailed.

Mr. Rich's legal troubles can be traced to the oil crisis in 1973. As the Arab oil embargo drove crude prices through the roof, the United States sought to stabilize the market with a complex system meant
to cap prices and increase domestic production. Department of Energy regulations created three classifications of American crude: Oil from “old” wells pumping at or below 1972 production levels could sell for no more than $8 a barrel. Oil from “new” wells — those opened since 1973 or producing in excess of their 1972 levels — was capped at about $10 a barrel. And “stripper” oil — from small wells pumping less than 10 barrels a day on average — went for whatever the market would bear.

The opportunity for gaming the system was clear. Before long, some traders were buying old or new oil for as little as $6 a barrel and — through a complex series of numerous transactions known as daisy-chaining or flipping — and in effect selling it as stripper oil for as much as $40 a barrel. Mr. Copetas's book says the Energy Department estimated that between 1973 and 1981, such maneuvers added up to at least 400 million $6 barrels being sold at stripper oil prices. Along the way, the number of oil resellers in America exploded. Before the Arab oil embargo, there were only 12 oil resellers in the U.S. By 1978, 500 companies were in the business.

One of those firms was West Texas Marketing, an Abilene, Texas, reseller whose owners later pleaded guilty to buying and selling daisy-chained crude. One of its buyers was Mr. Rich and his partner, Pinky Green. The WTM daisy chain fell apart in 1981, when federal prosecutors caught WTM illegally recertifying price-controlled domestic crude oil unrelated to the company's involvement with Mr. Rich.

As later described by prosecutors in court papers and news releases, Messrs. Rich and Green oversaw a massive scheme to evade price and profit controls and corporate income taxes through numerous “sham transactions” covered up by “false invoices” and fraudulent sales reports to the Energy Department. The illicit profits, sometimes after being secretly parked in the accounts of cooperative resellers, were spirited out of the country through additional “sham transactions,” so the Rich companies could evade United States taxes on them, prosecutors said.

Moreover, prosecutors said they discovered that the Rich operation had dealt in Iranian oil during the 1979-81 hostage crisis, after President Carter imposed a trade embargo. Rich officials in Switzerland argued that the ban didn't apply to Marc Rich & Co. AG because it was a Swiss company.

The investigation of Mr. Rich was relentless. For much of it, Mr. Weinberg worked under Rudolph Giuliani, then the hard-charging United States Attorney for the Southern District of New York who is now the city's mayor and was once Mrs. Clinton's acid-tongued rival for the Senate seat. Mr. Weinberg called 50 witnesses and subpoenaed more than a million documents. The Rich team, which included the late Edward Bennett Williams, dug in, adopting what Mr. Quinn conceded in a 1999 letter to prosecutors was “a most unfortunate no-communication, no-cooperation, no-negotiation strategy” for which “Mr. Rich has paid dearly.”

Mr. Williams made a last-ditch attempt to stave off the pending indictment of his client in mid-1983.  “The first time I met Ed Williams, he offered (a settlement of) $100 million for this to go away — no charges against the individuals,” recalls Mr. Weinberg. “And I said something to the effect of J-A-I-L. There is no way we're doing that. We could never bring another tax case if we allowed people to in essence buy their way out of it.”

In September 1983, Mr. Weinberg secured a 51-count indictment — later increased to 65 counts — charging Messrs. Rich and Green with racketeering, mail and wire fraud, tax evasion and, for dealing with Iran, trading with the enemy. But by then Messrs. Rich and Green were back in Switzerland, where the charges weren't extraditable offenses.

On Oct. 10, 1984, two Rich companies pleaded guilty to a total of 78 counts — 38 counts each of false statements in a scheme to circumvent profit controls and to evade taxes on $100 million and, for one company, two counts of dodging $48 million in taxes. The companies agreed to pay a $150 million settlement and $813,000 in fines and court costs, to forfeit $21 million in contempt fines and to forgo income-tax deductions on the settlement worth about $30 million more.

For Mr. Rich, exile from the United States was a galling smear. He achieved enormous success. At one point, his trading operation was doing $30 billion a year in more than 125 countries, employing 1,200 in 40 offices around the globe. Mr. Rich is estimated to have a net worth in excess of $1 billion.

But he couldn't set foot on American soil without fear of being sent to jail for years. Prosecutors refused repeated attempts to open negotiations, insisting that Messrs. Rich and Green return to the United States first. Mr. Rich wasn't even allowed to visit his leukemia-stricken daughter Gabrielle in  the months before she died at the age of 27 in 1997, the pardon application says.

A significant player joined the Rich legal team in 1999: Mr. Quinn served as a top aide to Al Gore in 1993-95 and as Mr. Clinton's top White House lawyer in 1995-97. He was a key player in defending the Clinton administration in many of its biggest legal fights.

Mr. Quinn made a couple of last attempts in 1999 and 2000 to open settlement talks with prosecutors. In October, the lawyers decided that “only the president could resolve this impasse,” Mr. Quinn recalls. Though prosecutors on the case have said they were blindsided by the pardon, Mr. Quinn says he told Deputy Attorney General Eric Holder on Nov. 21 that he planned to seek a pardon.

Mr. Quinn encouraged his clients to solicit letters explicitly endorsing the pardon request or at least praising their charitable works.

The most intriguing submission in the Dec. 11 application was a letter from Denise Rich. She wholeheartedly backed the petition, saying Mr. Rich “has a good and giving heart.”

Her feelings for him haven't always been so kind.

Ms. Rich, 57, had three children, and the family lived together in Switzerland until she sued for divorce in 1992, reportedly seeking $500 million. In an interview with Swiss magazine at the time, she declared: “Marc Rich destroyed our family. For 25 years, I was a loyal wife and dedicated mother. People gossiped, said he was a crook, but I stood by him. He shows his thanks by cheating on me with another woman.” Mr. Quinn declines to comment on Ms. Rich's statement.

The following year, she returned to the United States with her three daughters. Her relationship with the Democratic Party dates back almost to the first year she set foot back on American soil. Since then, she has donated $1.1 million to Democrats and their causes, including $120,000 to support Mrs. Clinton's race and $25,000 to Al Gore's Florida recount effort.

In a statement, Ms. Rich insists that her fund-raising efforts “have absolutely nothing to do with the pardon.”

The Riches' bitterly-contested divorce wasn't finalized until 1996. “It was not a friendly resolution,” says Martin R. Pollner, a lawyer for Ms. Rich. The daughter's death “acted as a spiritual reawakening to both” and “they made peace.” She supported the pardon because she wanted to assure her two other daughters “some sort of a normal life,” says Mr. Pollner.

Things came to a head as the Clinton years came to an end.

On Inauguration Eve, Mr. Clinton's last night in office, Mr. Quinn was sitting down to dinner at a friend's home. A phone call from the president interrupted the gathering. For nearly a half-hour, he quizzed Mr. Quinn about the Rich case. Mr. Quinn says the president was sympathetic to the argument that Mr. Rich's case should have been a civil, rather than criminal, matter, but was troubled by the appearance that Mr. Rich would escape further government scrutiny. At the president's insistence, Mr. Quinn skipped dinner and drafted a letter promising that Messrs. Rich and Green “will not raise the statute of limitations” if the Energy Department seeks to fine them in a civil action.

With the final hours in the Clinton administration ticking away, the White House counsel's office called the Pardon Attorney's office at the Justice Department with a list of names under consideration, including Mr. Rich's. The pardon attorney had to conduct a rushed FBI background check on all the names, as is customary. But there wasn't time to make a formal recommendation on the Rich case.  The department has informal guidelines for considering whether to back pardon requests. In general, pardon candidates are supposed to have been convicted, to have exhausted all appeals, to have completed their sentences and to live in the United States.

Messrs. Rich and Green satisfied none of those guidelines. A senior Bush official says lawyers are researching whether the pardons can be reversed, but legal experts say that's probably impossible.  The president's pardon authority is enshrined in the Constitution. For his part, Mr. Clinton credits Mr. Quinn with persuading him to pardon his clients. “I spent a lot of personal time ... because it's an  unusual case, but Quinn made a strong case, and I was convinced he was right on the merits,” Mr. Clinton said the day after leaving office.