On Sunday, in the airport of a city he does not want identified, Hilvan Finch acknowledged quietly that today, as he enters D.C. Superior Courtroom No. 3, he may be spending his last day as a free man.

There, Finch, a 30-year-old equipment salesman, will listen once again as government prosecutors argue that he belongs in prison for his participation as a Hanafi Muslim in the 1977 taking of more than 100 hostages at the B'nai B'rith headquarters here.

For Finch, today's court proceeding may be the last chapter of the siege that paralyzed Washington for 72 hours. It has been a fascinating tale, one of a battle over the nature of crime and punishment, pitting theories of retribution against those of rehabilitation, the public good against the individual with a secret so well kept from neighbors and employers that he asks that his home town not be identified.

In the middle of it all is Judge Nicholas S. Nunzio, a diminutive former prosecutor once known as "no-nonsense Nunzio," who first sentenced Finch -- known then as Abdul Hamid -- to a minimum of 36 years in prison and then three years later released him, saying Finch had "great potential for doing much good in this world."

It was a startling decision, and federal prosecutors eventually persuaded a higher court, the D.C. Court of Appeals, to order Finch back to prison, an order Nunzio refused to follow. Ever since, Nunzio, never known as a man to succumb to pressure, has been locked in battle with the higher court and prosecutors as he has attempted to find a compelling legal argument to keep Finch free.

So far, he has been unsuccessful three times -- twice he was ordered by the Court of Appeals to return Finch to prison, and in a third attempt he withdrew his own order after an argument in similar case failed with the higher court. But he has not ended Finch's freedom.

Today, said Finch's lawyer Timothy Junkin, Finch is down to his last untested argument. If he fails today, or wins today and then loses at a higher level, Finch may be in prison until 2017, when he will be 62.

For federal prosecutors the goals are simple: Return Finch to jail and in the process demonstrate to others that terrorism will be treated severely and harshly.

"We will show the need to deal strongly and decisively with terrorism in all its forms," said U.S. Attorney Joseph E. diGenova.

Finch, for his part, has been acquiescent. Though prosecutors predicted he would flee the country, he has returned voluntarily each time for his court appearances.

"Where would I run to?" he asked, sitting in an airport cafeteria, smoking cigarette after cigarette during a four-hour interview. "The thing is I guess I have the ultimate faith that . . . even though the judicial system is not as perfect as it should be, I have the sense of hope that someone is really going to sit down and look at this, just like Judge Nunzio obviously had to do at some point, and just look at it and see the individual . . . . "

Terrorism, he said several times, is an awful crime that victimizes innocent people. But, he contended he is not a terrorist -- just an unguided young man who made a terrible mistake, for which he said he is deeply sorry.

The controversy that has followed Finch over the years centers on the anger of a number of former hostages and on the violence of the takeover that brought the District to a halt for three days. For the hostages, Finch is a terrorist who held guns to their heads, pistol-whipping one and striking another.

On March 9, 1977, seven Hanafi Muslims siezed the headquarters of the B'nai B'rith, one of the nation's largest Jewish organizations, while others took over the District Building and the Islamic Center on Massachusetts Avenue NW. By the end of the siege, reporter Maurice Williams of WHUR radio had been killed and Mayor Marion Barry (then a City Council member), a council aide and a security guard had been wounded.

"We just don't think it's fair," said one former hostage who still works at the B'nai B'rith headquarters along with about 40 others who were present that March day, and who asked not to be identified in this article. "It's not justice."

At the time of his trial and during his sentencing Finch did not testify. For his participation, he was sentenced by Nunzio to 36 to 108 years and sent to a federal prison in Lompoc, Calif. It was at that point, freed from what he called the threat of death, that he began to communicate with Nunzio, calling himself a "hostage" of sorts.

Finch wrote Nunzio that he had been beaten by his father and had lived in a series of foster homes in New York when he was invited to come to Washington in the early '70s to live with Hamaas Abdul Khaalis, the leader of the Hanafis. In Khaalis, he wrote, he found a father figure who encouraged him to enter a military preparatory school in Virginia.

But life with Khaalis took a tragic turn after seven members of Khaalis' family were massacred by another Muslim group. Finch said he then never left the 16th Street home until he took part in the events that led up to the 1977 takeover.

In his letters, Finch insisted that he never knew he was being brought to the B'nai B'rith building and that although he rounded up and guarded the hostages, he "never intended to hurt anyone." He admitted he punched one hostage, but said he did so under duress. He says he unloaded his gun because he feared someone might get hurt.

Government prosecutors disputed Finch's portrait and argued that Finch was a willing participant who attempted to block police and injure others, pistol-whipping one of the hostages with the butt of a gun.

But after a hearing in 1981, Nunzio sided with Finch and gave him his freedom, saying he was convinced Finch had participated in the takeover "under severe distress" and that he had secretly aided a number of the hostages.

The decision sparked criticism of Nunzio and four years of legal flurry. Four months later the appeals court reversed his order. Nunzio again ordered Finch free, citing ineffective assistance of counsel. The higher court overturned that ruling in 1983.

Earlier this year Judge Nunzio reduced Finch's sentence for the third time, only to withdraw that order and set a hearing for today on Finch's argument that he was deprived of a fair sentencing because the judge did not have any information about Finch's involvement or history.

Today, Finch lives in a metropolitan area working in an entry-level sales job for an equipment company.

Finch said he does not belong to any religious organizations now and lives a spiritual life based on optimism. He said he lived in New York soon after his release in 1981 and then returned to Washington for several years under a court order, from which he was released recently. Finch said he does not want his workplace or home identified because neither his employers nor the people with whom he lives know about his past.

Those first few years, he said, his jobs were for the minimum wage he worked at minimum-wage jobs, which he lost whenever and anytime his name appeared in the newspaper he would lose his job.

"I look on that day," he said, "as if someone was walking through the airport and was bumped so hard that he almost fell to the ground. That person might be really angry, but when he looked up and saw that the man was blind, his anger dissipated . . . . In a way, I had such a handicap that day."