Connecticut prosecutors on Wednesday will ask the state's top court to reinstate the 2002 murder conviction of Kennedy family member Michael Skakel, three years after an appeals court ordered a new trial in the four-decade-old murder case.

Skakel, the nephew of Robert F. Kennedy's widow, Ethel Kennedy, has been free on a $1.2 million bond since 2013 after serving 11 years in prison in the 1975 slaying of Martha Moxley. Skakel and Moxley were neighbors in Greenwich, Connecticut, and both 15 when she was beaten to death with a golf club.

Skakel, now 55, was arrested in 2000, convicted in 2002 and sentenced to 20 years in prison. He persuaded an appeals court in 2013 to overturn his conviction, arguing that the lawyer who represented him at the time did a poor job.

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His current attorney, Hubert Santos, wrote in filings ahead of Wednesday's arguments in Hartford that the case against his client was based on two witnesses "of dubious credibility, who came forward with their preposterous stories of confessions after 20 years of silence and the announcement of a reward."

Santos argued that Skakel's original lead attorney squandered resources during the trial and was more focused on winning fame than his client's freedom. He contended that Skakel's trial defense team should have presented evidence that there were other suspects in the case, including Skakel's brother, Thomas.

State prosecutors argued that Skakel's new lawyers failed to prove that all, not just some, defense attorneys would have focused on other suspects.

"After careful consideration, the defense team decided that they did not have sufficient admissible evidence to present such a defense," Connecticut prosecutors wrote in a filing with the court prior to Wednesday's arguments.