The mysterious drowning of Natalie Wood on November 29, 1981, has been much speculated since her death.

Though it may never be clear what happened in the waters off Southern California’s Santa Catalina Island, TMZ reports that Natalie Wood’s death certificate has been changed from “Accident” to “Undetermined”.

TMZ reports that they were told by members of Natalie Wood’s family that L.A. County Sheriff’s Department detectives informed them of the change earlier today.

The family members were told that while Natalie Wood’s cause of death was irrefutably from drowning, they said that it is unclear how the actress got into the water.

The day the actress died, Natalie Wood was spending time with husband Robert Wagner and actor Christopher Walken both on Catalina Island and drinking on the yacht.

Robert Wagner said in the 1981 autopsy report that his wife “was not suicidal”.

He has dismissed suggestions that the actress’ death was anything other than an accident.

Natalie Wood’s death certificate has been changed from “Accident” to “Undetermined”

Natalie Wood and fellow actor Robert Wagner were married twice, first in 1957 before divorcing six years later. They remarried in 1972.

Her death during the Thanksgiving weekend in 1981 has long sparked tabloid speculation that foul play was involved. Rumors were reignited by author Marti Rulli, whose book, Goodbye Natalie, includes a fresh account of the incident by the yacht’s captain, Dennis Davern.

Dennis Davern has come forward to say he lied to investigators in the wake of the tragedy, and suggests Robert Wagner ensured the investigation was not as thorough as it could have been.

Asked on the Today show if he thought Robert Wagner was responsible for Natalie Wood’s death, Dennis Davern replied: “Yes, I would say so. Yes.”

“We didn’t take any steps to see if we could locate her. I think it was a matter of: <<We’re not going to look too hard. We’re not going to turn on the searchlight. We’re not going to notify anybody right now>>.”

“I made terrible decisions and mistakes. I made mistakes by not telling the honest truth in a police report.”

In a dossier on the case Dennis Davern and Marti Rulli have now sent to police, they claimed there was “a drastic delay” in calling for help after Natalie Wood went missing.

“There are many, many things that should be examined, but mainly the four-hour wait to call for the coastguard,” Marti Rulli said on CNN.

Dennis Davern maintains that, after the stand-off between Robert Wagner and Christopher Walken, husband and wife went to their state room, from which the skipper heard sounds of a heated argument and “thumping”.

Later, Dennis Davern went back on deck to be told by Robert Wagner that Natalie Wood was missing, along with the yacht’s dinghy.

Natalie Wood’s body was found hours later, floating in an upright position, her eyes fixed and open, her spectacular, long, dark hair trailing along the surface of the water. She was wearing a flannel nightgown, red down jacket and blue woolen socks.

Meanwhile, caught up in seaweed in a cove not far away was the missing dinghy, its oars in place and the key in the ignition in the “off” position, suggesting she had never made it into the boat or, if she had, had quickly fallen out.

Robert Wagner apparently thought she might have been heading for the shore, where there was a bar, or gone party-hopping to one of the other rich people’s boats moored nearby.

Later he suggested she had not been trying to leave the yacht at all, but that she had heard the dinghy slapping against the side of the boat and had gone to secure it more firmly, only to fall in.

Police concluded that the two dozen bruises on her body, including cuts on Natalie Wood’s face, were sustained when she fell overboard and struggled in the water.