Half a century has passed since the tragic death of a young girl from a prominent Connecticut family, yet the mystery surrounding her murder lingers. The case involves a Kennedy family member who was initially found guilty but later had his conviction overturned.

Michael Skakel, a relative of Robert F. Kennedy Jr., served over a decade in prison for the 1975 murder of 15-year-old Martha Moxley. Despite the conviction, Skakel has consistently maintained his innocence. He is now sharing his side of the story in a newly released NBC News podcast, “Dead Certain: The Martha Moxley Murder.”

Martha Moxley’s life was tragically cut short on October 30, 1975, when she was brutally murdered with a golf club. That evening, she was spending time with friends during Mischief Night, an occasion when teens traditionally engage in playful pranks before Halloween.

Witnesses reported seeing Moxley interacting with Thomas Skakel, Michael’s older brother, that evening. According to the Hartford Courant, the two were observed at around 9:30 p.m. “falling together behind the fence” near the Skakel family’s swimming pool.

Image of Martha Moxley at age 14. (Photo Credit: Erik Freeland/Corbis via Getty Images)

The next day, Moxley’s battered body was discovered with her pants around her ankles, alongside a broken golf club under a tree on her family’s estate, according to The Associated Press. 

An autopsy later revealed Moxley had been beaten and stabbed to death with the golf club, which was ultimately traced to the Skakel family’s home. 

Initially, investigators pointed to Thomas as the primary suspect in Moxley’s murder, before turning to the Skakel children’s live-in tutor, Kenneth Littleton. However, neither man was ever charged with a crime.

Michael Skakel reacts to being granted bail during his hearing at Stamford Superior Court November 21, 2013, in Stamford, Connecticut.  (Bob Luckey-Pool/Getty Images)

Their focus eventually shifted to Michael Skakel, and 15 years later, on Jan. 19, 2000, he turned himself in to authorities after police issued a warrant for his arrest. 

“This is what I call the cross-finger pointing problem, when only two people in the family are the suspects,” Wendy Murphy, a professor at New England Law Boston, told Fox News Digital. “In the whole world, we only have these two suspects and they’re family, so they stick together like glue. [If] they both take the Fifth and they agree to be each other’s built in reasonable doubt, you’ve got a problem.” 

Michael Skakel was ultimately charged with Moxley’s murder and arraigned as a juvenile, since he was 15 when the killing took place. The case was later moved to regular court.

A photo from the trial evidence showing a close-up of the golf club head.  (Pool Photo/Getty Images)

A photo from the trial evidence showing a close-up of the golf club shaft.  (Pool Photo/Getty Images)

During his arraignment, Skakel, who was 39 at the time, pleaded not guilty and reportedly approached Moxley’s mother before telling her, “You’ve got the wrong guy.” 

Two years later, on June 7, 2002, Skakel was convicted of murder by a panel of 12 jurors in Norwalk Superior Court. He was sentenced to 20 years to life in prison. 

However, questions remained regarding Skakel’s guilt – and his ability to accurately recount a crime that was committed nearly three decades before.

The Moxley residence in the Bellehaven section of Greenwich, Connecticut, in 1975.  (MediaNews Group/Boston Herald via Getty Images)

“When he was convicted, it was 27 years after the murder,” John Clendening, author of “Julia’s Angels,” told Fox News Digital. “So, just imagine you being called as a witness in a trial in 2002. How much do you really remember about a certain night when you were 15, 16, or 17?” 

In 2013, following multiple failed attempts to appeal his conviction, Skakel was granted a new trial after a judge ruled his attorney, Michael Sherman, did not adequately defend him in his original case. 

Skakel’s murder conviction was ultimately vacated by the Connecticut Supreme Court on May 4, 2018, with prosecutors later deciding to not seek a second trial for Skakel on the murder charge.

Skakel, Sherman and NBC News did not immediately respond to Fox News Digital’s request for comment. 

Kennedy relative Michael Skakel gets into a car after walking out of a Stamford, Connecticut, courthouse after his murder conviction in the death of Martha Moxley was vacated when a judge decided he did not receive adequate representation in his 2002 trial on Nov. 21, 2013. (Spencer Platt/Getty Images)

However, Moxley’s brother, John Moxley, has vocally denounced the court’s decision. 

“Just because he’s out on the street doesn’t mean what we know isn’t right,” he said in “Murder and Justice: The Case of Martha Moxley,” a three-part documentary on his sister’s life and death. 

“Where we are now is that it’s all about judges and technicalities. It’s not about who killed Martha. At this point, him being out doesn’t change anything for me. And he’ll be in prison for the rest of his life regardless of where he’s walking the streets. He will be in his own prison for the rest of his days.”

Following Skakel’s second chance at freedom, the mystery surrounding Moxley’s death remains – with listeners awaiting the chance to hear Skakel’s story in his own words. 

“I think what’s going on here is [Skakel] sees an opportunity to get his side of the story out there, and I can’t blame him for that at a time when the world is revisiting the crime,” Clendening told Fox News Digital. “He’s only going to have so many opportunities to do that. So I think that’s what’s going on. I think he sees an opportunity to tell his side of the story.”