NEW HAVEN, Conn. (AP) – A man who implicated two friends in the 1975 murder that sent Kennedy cousin Michael Skakel to prison has refused to testify, prompting a prosecutor Thursday to accuse him of making up the account.

Gitano “Tony” Bryant invoked his Fifth Amendment right against self-incrimination at his deposition last week in Miami and does not plan to testify at upcoming hearings on whether Skakel deserves a new trial, said Joel Denaro, his attorney.

“What it strongly suggests to us is that Mr. Bryant’s story is a fabrication and he is seeking to avoid testifying under oath for that reason,” prosecutor Jonathan Benedict said.

Skakel’s attorneys have said, in court papers, that Bryant implicated two of his friends in the bludgeoning death of 15-year-old Martha Moxley. Skakel, who was 15 and a neighbor of Moxley’s at the time of the murder, was convicted in 2002 of bludgeoning Moxley with a golf club and is serving 20 years to life in prison.

Bryant’s claim in 2003 was the latest sensation in a case that sparked numerous books and criticism that local authorities showed too much deference to Skakel’s wealthy connected family during the initial investigation.

Hope Seeley, Skakel’s attorney, said she will file a motion seeking to compel Bryant to testify.

“I think the fact that Mr. Bryant asserted his right against self incrimination was not surprising once he hired a criminal defense attorney in light of the fact that he placed himself at the crime scene the night of the murder holding a golf club around the time of the murder,” Seeley said.

Seeley noted that her defense has a videotaped interview of Bryant giving his account. She said Bryant’s credibility was up to a jury to assess.

“I think it’s inappropriate for the state’s attorney to be issuing statements about a person’s credibility,” Seeley said.

Denaro would not comment on whether Bryant stands by his account.

“After advice of counsel, Mr. Bryant has exercised his Fifth Amendment right to remain silent,” Denaro said. “We’ll be taking the Fifth Amendment in any and all proceedings.”

Skakel, a nephew of Ethel Kennedy, is seeking a new trial based on a claim by Bryant that two of his friends may have killed Moxley.

The men, Adolph Hasbrouck and Burt Tinsley, earlier exercised their Fifth Amendment rights.

Neither of the men has returned repeated telephone calls. Hasbrouck’s wife, who declined to give her name, said at the couple’s home recently that the allegation was “a lie.”

“He didn’t do anything. My husband is a good man,” she said.

Bryant attended private school with Skakel when they were teenagers. His allegation surfaced in 2003, a year after Skakel was convicted of killing Moxley in their gated neighborhood in Greenwich when they were both 15.

According to Skakel’s attorneys, Bryant said he was with two friends from New York in that neighborhood the night Moxley was killed. According to court papers, Bryant said one friend had met Moxley and “wanted to go caveman on her,” and that after he left them that night, they later told him, “We did what we had to do.”

Bryant’s refusal to testify is a setback for Skakel, said Steven Duke, a law professor at Yale University.

“If he persists in taking the Fifth and is allowed to take the Fifth, they have to find some other evidence to link these two folks with the murder because his hearsay is not likely to be enough to get them a new trial,” Duke said.

But Duke said he would not draw any inference about whether Bryant was telling the truth because he took the Fifth.

Some of the questions asked by Skakel’s attorneys during the deposition were “accusatory in nature” toward Bryant, his attorney said.

Seeley said Skakel’s defense was not accusing Bryant of committing the crime.

“Our position is Tony Bryant came forward with information that should be put in front of a jury,” Seeley said.

Bryant’s move also sets up a fight over whether his initial statement to Skakel’s investigator, Vito Colucci Jr., will be admissible.

In 1992, Bryant claimed he had been kidnapped when he was questioned about an armed robbery in Beverly Hills, Calif., police records show. Bryant pleaded no contest to the charge of accessory to a felony larceny and served six months of home monitoring.

In the late 1980s, Bryant was hired as an attorney in Texas but colleagues say he was later fired after they learned he was not licensed.

“We have so much information with which to confront Mr. Bryant,” Benedict said.

The petition for a new trial is separate from an appeal Skakel lost before the Connecticut Supreme Court earlier this year that argued, among other issues, that the five-year statute of limitations had expired when he was charged in 2000. Skakel’s attorneys have taken that issue to the U.S. Supreme Court.

Skakel’s attorneys are trying to depose Frank Garr, who investigated the case for the state and later cooperated with a reporter on a book about the crime. They want to know if Garr received any money from the book and are seeking documents related to the investigation that they say are at Garr’s home and were withheld from prosecutors and defense attorneys.

“Documents regarding inspector Garr’s involvement with a book about the prosecution of Michael Skakel would undoubtedly be highly relevant to his interests, financial or otherwise, in a guilty verdict in the case,” Skakel’s attorneys wrote. “Participation in a book arguably colors his decision-making process to turn over or withhold exculpatory evidence, speak with or decline to interview various witnesses, or even eliminate other possible suspects.”

Prosecutors called the request overly broad and irrelevant. Benedict denied Garr withheld any information and called him an effective investigator.

Telephone messages were left Thursday for Garr at home and his office.