The Connecticut Supreme Court has ordered a new trial for Kennedy cousin Michael Skakel, who was convicted in 2002 for the 1975 murder of Martha Moxley, according to The Associated Press.

Friday’s 4-3 court decision vacated Skakel’s earlier conviction and ruled Michael Sherman, Skakel’s trial attorney, was not successful in presenting evidence of a possible alibi. As a result of the decision, the court’s previous 2016 ruling, which reinstated Skakel’s conviction following a lower court’s order for a new trial, was overturned.

Skakel was accused of bludgeoning Martha Moxley to death in 1975 in Greenwich, Connecticut, while both were in their teens. After being handed a 20-year prison term, he was released on bail following a lower court’s decision to overturn his murder conviction in 2013.

Skakel is the nephew of Ethel Kennedy, who was married to Robert F. Kennedy. The well-known name and his wealthy family have generated international attention to the case, as well as a number of theories about who killed Moxley and the brutal way in which she died.

Justice Richard Palmer, who wrote for the majority on the decision, said Skakel was biased against due to the fact that his attorney didn’t get alibi testimony from witness Denis Ossorio. “Without Ossorio’s testimony, the state was able to attack the petitioner’s (Skakel’s) abili – a complete alibi for the time period during which it is highly likely that the victim was murdered – as part of a Skakel family conspiracy to cover up the petitioner’s involvement in the victim’s murder,” Palmer wrote.

Hubert Santos, an appellate lawyer representing Skakel, asked the court to re-examine its ruling reinstating the conviction. Santos maintained Sherman, Skakel’s previous lawyer, did not make good decisions in the case, saying he did not focus on Skakel’s brother, Tommy, as a possible suspect and did not attempt to get in touch with an alibi witness. He claimed his client was miles away from the area when Moxley was killed.

Santos also argued there was no physical evidence or eyewitnesses connecting Skakel to Moxley’s murder.

Sherman has defended his work and state prosecutors have argued he did an adequate job.