PAUL M. Williams is the kind of man who preaches when he talks about the work he loves. One moment he will be reeling off statistics about how expensive it is to keep a man in jail; the next moment he will be remembering what it felt like "to hear the cell door close at night."

While serving nine months of a prison sentence two years ago, Williams saw dozens of men who didn't have "anything on their young minds past prison," and whose chances of returning were very good. It was then he decided to work with ex-offenders once he got out.

"I'll never be rich doing this, but I came to a decision that it's going to be working with these young kids," said Williams.

Williams, out on bond pending appeal after being convicted of drug conspiracy 2 1/2 years ago in New Jersey, is a restirution counselor at Inner Voices, a self-help agency in the District that aids ex-offenders during the transition from prison to thecommunity.

Ironically, yesterday, the 34-year-old Williams was sent back to prison. New Jersey appellate judges affirmed the 10-15 year sentence and the New Jersey Surpreme Court refused in December to hear the case.

He is returning to jail in spite of letters to the judges from officials in the criminal justice community lauding Williams for his work with ex-offenders and his responsible behavior.

And, ironically, the judge rejected any suggestion of an alternative to a prison sentence -- such as weekends in jail along with community work -- for a man who works with these kind of alternatives every day.

Williams grew up in the Edgewood Terrace area of northwest Washington, attended Roosevelt Senior High School and knows the life and the language of the streets. He is a 6-foot-5 Vietnam veteran, and can tell you about prison life and drugs. There aren't many ex-offenders who can manipulate him or fool him.

The difference between him and many of the ex-offenders he works with is that Williams has been working steadilysince his graduation from Federal City College in 1972 with a BA in community planning and development, and has plans to become a lawyer. At the time of his arrest, he was a partner in an ad agency called Ku-umba Advertising.

William's troubles began in June 1976 when, he says, he went to Egg Harbor, N.J., to buy cocaine. Federal agents had staked out the house and arrested Williams and his companion, charging them with conspiracy to distribute cocaine and possession of cocaine.

Williams and his companion were accused of supplying large quantities of cocaine to a New Jersey contact over aperiod of several months. Williams claims that he was not dealing in cocanine and that he went to New Jersey to buy drugs for his own use. However, Williams says he bought no drugs on this occasion and had no drugs in his possession when he was arrested.

After being out on bond for 16 months, Williams was indicted on seven counts of possession and conspiracy to distribute cocaine based on evidence obtained from a police investigation. The case resulted in a hung jury, but the judge ordered its members to make a decision. The jury found Williams guilty of drug conspircy, but not of possession.

The judge sentenced Williams to 10-15 years in jail, and sentenced his co-defendant, a white man, to 5-7 years in jail.

Williams then served "nine months, three weeks and one day" in the Leesburg State Penitentiary, in Cumberland County, N.J., after making bond pending appeal, he returned to Washington where he got a job with Inner Voices.

Since then, Williams has been working as a restitution coordinator, counselor and job devloper for groups ofabout 60 to 65 offenders who are given to the program by the courts as an alternative to jail. Williams is responsible for monitoring their behavior, helping them find employment and seeing that they do a certain amount of volunteer work as restitution.

Also during this time, Williams sayshe spent about $30,000 appealing the case, obtaining the money from his salary and from a fund set up by his friends called the Committee for the Defense of Paul Williams. At the beginning of this month, New Jersey Superior Court Judge Manuel Greenberg, who originally sentenced Williams, refused to modify the sentence at a sentence reduction hearing.

Most persons familiar with the case say the sentence is excessive and that the judge could have reduced the sentence based on Williams' good behavior since his conviction.

Williams asked Matthew G. Yeager, an asistant professor at George Washington University, to examine whether he would find him a suitable candidate for a community-base sentence. Yeager also is a consulting criminologist specializing in the sentencing of felonyoffenders.

Yeager suggested that Williams be given a suspended prison sentence and placed on active probation for at least five years, fined and ordered to provide several years of community service working with offenders. Yeager said that if the court felt incarceration were necessary, he would recommend jail on weekends for perhaps six to seven months.

Williams says he feels that the discrepancy in sentences, and the fact that the judge would not modify or reduce the sentence, points to racism.

"the judge told me that since the profits for drugs are so vast, the penalty for them whould be very stiff," said Williams. "i have no problem with that But when I asked him why my sentence was longer than my codefendant's, he told me he didn't have to tell me anything and the hearing was over. If he gave me 5-7 (years), I wouldn't have such a problem. If I had been white with the rest of those white boys, I would have gotten 5-7 years."

Court transcripts indicate that Greenberg believed Williams was much more involved in the conspiracy than his codefendant.Mary Jane Cooper, deputy general of the division of criminal justice in the appellate section in New Jersey, said court transcripts also indicate Judge Greenberg took into consideration the fact that Williams had once been convicted of robbery.

At the reduction in sentence hearing Judge Greenberh said: "I've considered the matter carefully and I still feel that in the interest of deterrence the sentence that was imposedshould be carried out."

However, "the (appellate) judges didn't adequately take into consideration the defendant's background" in considering a modification of sentence, said James Plaia, a New Jersey attorney who served as Williams' counsel during the appeal. "There's nothing in Williams' background to justify the sentence. His background is such that he should be commended."

Plaia believes that if Williams was tried today, he would not have received such a severe sentence.

"With the social climate at this point regarding drugs, I think there would have been a different result. Community standards seem to be a little more lenient in terms of cocaine," he said.

Letters written by professional associates of Williams to verify Williams' good behavior describe him as a "competent, concerned and responsible professional," who has "provided firmness, strength and friendly concern to men who have become isolated." And, "We are all very distressed at the possibility of losing Paul."

Shellie R. Fine, a program developer with the District's public defender service, wrote, "I find that his (Williams') prior criminal activities are in no way representative of his current lifestyle, character and forward direction."

John C. Dillingham, director of special projects in the Washington School of Psychiatry, who has worked with Williams, wrote, "(Williams) is an example of how a man can meet, face, and master the challenge of a previous involvement in the criminal justice system -- and how a man can put that behind himself, begin to repay the community for the costly mistakes of his past and, quite simply -- start over."

Many criminologists advocate alternative sentences for lawbreakers unlikely to commit violent crimes. Advocates argue that incarceration is costly (about $23,000 a prisoner a year) and ineffective as a deterrent to crime.

For instance, 19-year-old Alan Cole, the Maryland man convicted of committing manslaughter with an automobile when 10 of his friends were killed while he was driving a pick-up truck, never went to prison. The judge sentenced him to a program of drug and alcohol counseling, psychotherapy and three years of volunteer work in a Baltimore hospital emergency unit.

The only steps Williams can take now is to file for a governor's conditional pardon and to file a petition before the U.S. Supreme Court -- both long shots.

Williams says: "The problem I have with this whole thing is I feel my constitutional rights have been violated. It's kind of ironic that I've helped between 300 and 500 ex-offenders and it doesn't look like I can get much help.

"I got to go back and do that 10-15 years and if I'm lucky, and don't get shot or stabbed or beat up or whatever, I could probably be out in three to four years," he said.

Williams was planning to apply for Antioch Law School and was engaged to be married in the spring. Both will have to wait for three, four or maybe five years before he can get out of prison on parole.

"I was really breaking out of the actual monetary restraints that the trial had put me in," said Williams, "and this program (the rehabilitation program of Inner Voices) is growing in leaps and bounds. I feel like my entire life's work is out the door."