Connecticut prosecutors asked the state’s top court on Wednesday to return Kennedy family member Michael Skakel to prison to serve the last nine years of a sentence imposed after he was convicted of murdering a friend four decades ago.

Skakel, a nephew of Ethel Kennedy, widow of slain U.S. Sen. Robert F. Kennedy, has been under legal scrutiny since his neighbor Martha Moxley was beaten to death with a golf club near his Greenwich, Connecticut, home in 1975. Both Skakel and Moxley were 15 years old at the time.

Both Michael Skakel and his brother, Thomas, had been romantically interested in the girl and were regarded as suspects by police, as was a tutor who lived in the house. More than two decades passed before anyone was criminally charged.

Prosecutors charged Michael Skakel, now 55, with murder after three witnesses, including two people who had attended a controversial and violent Maine drug rehabilitation program with Skakel in the late 1970s, testified that Skakel had confessed to them that he had murdered Moxley.

He was sentenced in 2002 to serve 20 years in prison, but was released on $1.2 million bond in 2013 after a new attorney, Hubert Santos, persuaded a state court that the attorney who defended him at trial did a poor job.

“This defendant did not get a fair shake,” Santos told the Connecticut Supreme Court in Hartford on Wednesday, at a hearing on the state’s appeal of the 2013 decision.

Santos argued that his client’s original lead attorney squandered resources during the trial and was more focused on winning fame than his client’s freedom. He contended Skakel’s trial defense team should have presented evidence of other suspects in the case, including Skakel’s brother, Thomas, who was never charged. The tutor was also never charged.

Prosecutors, who are asking the court to order Skakel back to prison, disputed that account.

“This was far from a slipshod defense. This was a well-planned, well-thought-out defense,” said Susann Gill, a supervisory assistant state’s attorney. “It has always mystified me that there was a myth that has come up that this was a weak case. It was not.”

The court did not immediately rule.

Michael Skakel’s attorneys have said he is innocent.

Santos said on Wednesday the long delay in charging his client underlined the weakness of the evidence.

“It’s common sense. A 1975 murder, a 1999 arrest. No physical evidence, no witnesses, no DNA, no trace evidence,” Santos said. “You have to scratch your head, I would submit, and look at it in a very skeptical manner.”