The New Jersey Attorney General's Office has opened an investigation into the unsolved murder of a prominent couple who were killed in their home in 2014, WNYC and Gothamist has learned.

The development comes after a WNYC Studios podcast revisited the deaths of John and Joyce Sheridan, who were found in their bedroom early September 28th, 2014, stabbed to death and the room set on fire. The series, Dead End: A New Jersey Political Murder Mystery, has been reporting on the unsolved killings, the investigation into their deaths, and John Sheridan’s ties to New Jersey politics.

The victims’ family has repeatedly asked the state attorney general's office to get involved in the case. Local detectives working for the Somerset County Prosecutor’s Office initially believed the killings were a murder-suicide and never fully investigated the case, WNYC’s reporting found.

“Our office is investigating this matter, and we will follow the evidence wherever it leads,” said a spokesperson for the New Jersey Attorney General's Office. WNYC confirmed with the attorney general’s office that the investigation had been launched after three people connected to the couple said they had been contacted by a state investigator.

The Sheridan family had disagreed with the murder-suicide determination by local detectives from the start, and family members found numerous problems with the investigation in the days after the deaths.

“I'm happy to hear that they've started to reach out to people,” said Mark Sheridan, one of the couple’s four sons, when he was told by WNYC about the new investigation. “I didn't know that, but I certainly think it's a good start.”

In 2016, some 200 prominent citizens, including three former governors, a former state supreme court justice and two former attorneys general also called for the state to investigate.

The WNYC podcast details many of the questions raised about the original investigation. Detectives had concluded the case was a murder-suicide, in part, because the primary exit from the bedroom where the Sheridans were found dead was blocked. But there was a back door to the bedroom that would have allowed an assailant to exit the home. WNYC also found that the crime scene was not dusted for fingerprints, that blood spatter on a wall in another part of the home remained unexamined, and that the weapon that killed John Sheridan was never identified by local investigators. Another possible weapon, a fire poker matching John Sheridan's injuries, was later discovered by an insurance investigator.

“The circumstances of their deaths were very, very unusual,” said Ed Stier, an investigative attorney who helped create and run the Division of Criminal Justice at the attorney general's office. “And for the Somerset County prosecutor's office to walk into the crime scene and say, ‘oh, this is obviously a murder-suicide’ before any investigation took place was criminal negligence.”

Stier said strong criticism is warranted.

“I'm very upset about it because it’s completely irresponsible,” Stier said. “They couldn't have done a worse job if they intended to mess up that investigation. They destroyed the crime scene and made it impossible for anybody to come in later on and do any kind of decent forensic work.”

A state investigator and an FBI agent recently interviewed Bob and Chris Stevens, who were close friends of the Sheridans. Chris had lunch with Joyce Sheridan on the Friday before her death. The couple died sometime between Saturday night and sunrise Sunday morning.

“We really would rest easier if we knew that everything was resolved on this,” Chris Stevens said after being interviewed by investigators . “ It would be very comforting knowing that they finally figured out what the story was.”

John Sheridan had worked for two governors and served as the state transportation commissioner in the 1980s for Gov. Tom Kean, a Republican. He then worked as a lobbyist for a top law firm in New Jersey, and became the CEO of Cooper University Hospital in Camden.

The Sheridans’ sons said they asked for help from the attorney general at least three times. First, after detectives said they believed the case to be a murder-suicide. A second time when evidence in the home revealed multiple problems with the investigation. And the oldest son, Mark Sheridan, returned to the attorney general after he found documents that had been on his parents’ dining room table.

The documents included printed email exchanges and handwritten accounts of phone conversations and meetings related to a real estate deal on the Camden waterfront.

“My father was involved in a very high-dollar real estate transaction that was going to make lots of money for lots of people,” Mark Sheridan said. “I just think that, in that circumstance, it's something that should be investigated and looked into.”

For more on the Sheridan case listen to WNYC’s podcast Dead End: A New Jersey Political Murder Mystery.