NORWALK Michael Skakelís murder conviction stemmed from weak evidence, a poor job by his attorney and a prosecution driven by celebrities such as Dominick Dunne and Mark Fuhrman, Robert F. Kennedy Jr. argues in a new magazine article.

Kennedy, who is Skakelís cousin, makes the accusations in a 15,000-word article, "A Miscarriage of Justice," in the edition of The Atlantic Monthly scheduled to be released next week.

Skakel, 42, is serving 20 years to life in prison. He was convicted in June of the October 1975 beating death of his Greenwich neighbor, Martha Moxley. She was bludgeoned to death with a golf club when she and Skakel were both 15. Skakelís attorneys plan to appeal.

Kennedy writes that he knows Skakel as well as anyone, noting that they attended hundreds of alcoholism recovery meetings where they shared their deepest feelings. He credits Skakel with helping him get sober.

"I support him not out of misguided family loyalty but because I am certain he is innocent," Kennedy writes. "If he were guilty I would have testified against him."

Prosecutor Jonathan Benedict said the case against Skakel was strong. He noted that numerous witnesses testified that Skakel had confessed to the crime or made incriminating statements over the years.

"You put that all together and thatís what convicted him," Benedict said. "What sunk Michael Skakel was his own words."

Kennedy is better known as an environmental attorney. He attended little of the trial, but said to prepare the article he interviewed Skakelís siblings, his lawyers, other witnesses and investigators.

Over the years, as the case remained unsolved, observers have suggested that money and power somehow protected Skakel, whose fatherís sister is the widow of U.S. Sen. Robert F. Kennedy.

"The case has remained unsolved for so many years not because of Skakel family wealth, power and connections but because it is baffling," Kennedy writes. "This one was especially difficult because of a parade of more than 40 potential suspects."

Kennedy accuses Skakelís defense lawyer, Michael Sherman, of being more interested in publicity than his client. Before the trial, Kennedy writes, Sherman should have appealed a ruling rejecting his argument that there was a five-year statute of limitations for murders in 1975.

"An early victory in such an appeal would have deprived Sherman of the nationally publicized trial he expected would boost his career," Kennedy said.

Kennedy also accuses Sherman of trying to get Skakelís sister, Julie, to lie on the witness stand to boost Skakelís alibi; conducting weak cross examinations; failing to prepare his own witnesses; and failing to explain why Skakel changed his account of his movements the night of the murder. He also faults Sherman for selecting a police officer as a juror.

Sherman denied the charges. He said the defense team had agreed that the best time for an appeal was after the trial.

"When you win, youíre a hero. When you lose, youíre two notches below Satan," Sherman said. "Anybody who knows me knows how much I believe in Michael Skakel and how hard I fought and will continue to fight for his freedom."

Kennedy devotes much of the article to evidence against Kenneth Littleton, who had just started his job as a Skakel family tutor the night Moxley was murdered. Littleton failed repeated lie detector tests, changed his account of his movements that night and engaged in increasingly bizarre behavior in the years after the murder, Kennedy writes.

"I do not know that Ken Littleton killed Martha Moxley," Kennedy writes. "I do know ó and as a former prosecutor I understand the laws of evidence ó that the stateís case against Littleton was much stronger than any case against Michael Skakel."

Benedict said Kennedy exaggerated the number of lie detector tests Littleton had taken and said state police even refused to test him because of his mental illness. No evidence was ever developed incriminating Littleton, Benedict said.

"I have never seen anybody investigated as extensively as Ken Littleton was," Benedict said.