In the latest twist in a case that has been full of them, the Connecticut Supreme Court ruled on Friday that the murder conviction of Michael C. Skakel, who was found guilty in 2002 of bludgeoning a teenage neighbor with a golf club, should be reinstated.

[2018 Update: Connecticut Court Reverses Michael Skakel’s Murder Conviction]

The court said in making its ruling that Mr. Skakel’s original lawyer had, despite accusations to the contrary, represented him effectively.

The decision could send Mr. Skakel back to prison to finish a prison term of 20 years to life. He had spent more than a decade behind bars before he was released in 2013 when a judge vacated his original sentence.

Over the years, Mr. Skakel, a nephew of Ethel Kennedy, has attracted the attention of gossip columnists, TV crews and magazine writers as his case slowly moved through nearly every branch of Connecticut’s judicial system.