When a young astrophysicist died in Antarctica, his death was blamed on natural causes. Now, David Fisher investigates whether Rodney Marks' death was the first murder on the ice

Rodney Marks was buried for a second time under the warm Australian sun, in a bush cemetery not far from the beaches he surfed as a boy.

On a hill above the grave, a gum tree stands against blue skies. Close by is the beginning of the Great Ocean Rd, which chases the sun and surf west as Marks once chased his dreams, all the way to Antarctica.

It was there, in one of the world's coldest and most remote terrains, that Rodney Marks was buried for the first time. He died suddenly, and of all the questions that still surround his death, the most chilling is whether he is victim of Antarctica's first murder.

Marks, 32, died in May 2000 at the frozen Amundsen-Scott Station, the American base at the South Pole. His body trapped for the winter, Marks' friends made him a coffin of oak scavenged from around the base, planing and polishing rough wood into a 200kg casket.

As they mourned their friend, the elite American agency that runs the base, the National Science Foundation, issued a statement saying Marks had died of "natural causes". The statement was wrong, but it would be months before this was discovered.

In March each year, the sun sets on Amundsen-Scott Station, and in October it rises again. The 50 people, including Marks, were there for the long, isolated winter.

It wasn't until late October, on one of the first flights out, that Marks' body left Antarctica, travelling from Amundsen-Scott Station, through McMurdo Station to Christchurch in New Zealand.

There, an autopsy by Christchurch forensic pathologist Dr Martin Sage found that Marks died from somehow ingesting the equivalent of a large glass of methanol.

By the time this was discovered, the 49 people who left the South Pole alive had scattered across the world. Marks' living quarters had been cleaned up, and potential evidence discarded as rubbish.

With witnesses gone and evidence trashed, finding the answer to Marks' death fell to Detective Senior Sergeant Grant Wormald of the New Zealand Police. The investigation was to take eight years and, in the end, the questions remained.

Wormald did rule out some possible explanations.

It was highly unlikely to be suicide. Marks was in love with Sonja Wolter, whom he had met in Antarctica and planned to marry. An accident was also considered unlikely.

Coroner Richard McElrea's report ruled out none of these possibilities, and raised another.

"An alternative possibility is he drank methanol through a third person's actions, either in the form of a prank or with a more sinister motive."

The search for answers raised more questions. Why were there needle marks in the young scientist's arm? Why did the National Science Foundation - which answers only to the United States President - appear to block Wormald's inquiries?

Was it because Wormald's inquiry exposed an Antarctica different to the studious, academic centre that might be expected? Was it because he found an Antarctica where some of those isolated for six months of darkness drank heavily and used drugs?

Rodney Marks was clever. He grew up in Geelong, Australia, chasing surf on the coast south of the town, playing music, watching Aussie Rules football and being a Goth.

He moved to Sydney, attended the University of New South Wales studying astronomy. In 1994, he visited the Antarctic for the first time, returning in November 1997 to spend a year there working on a telescope project.

Dr Chris Martin, who worked on the same project and spent winters in Antarctica in 2001 and 2002, says the South Pole offers unique opportunities for astronomers.

"Rodney liked it so much he wanted to go back again."

So, in November 1999, Marks returned. He was among about 250 people who spent the summer at the base, with the number reducing as winter closed in. Of those remaining, only 10 were scientists, with the remainder forming a maintenance and management crew employed by the science foundation or its contractor, Raytheon Polar Services.

Marks and Sonja Wolter, then 33, were a lively couple, involved in the base band, Fannypack and the Big Nancy Boys. Marks dyed his hair purple, and Wolter's bright green.

Darryn Schneider, who spent the winter there, says "it is rare to see people that seemed so perfectly matched". The two became inseparable and as winter drew closer, Wolter was able to change her posting to spend the winter with Marks.

The last flight out left 50 people on the ice, settling into a routine for the winter as the sun slowly set.

On May 11, according to Wolter's statement to police, Marks felt unwell, said he had poor vision (recognised belatedly as a symptom of methanol poisoning), and "went to bed early, which was unusual".

Wolter says Marks woke during the night to take antacid tablets, before waking at 5.30am and vomiting blood.

The couple went back to BioMed, the base medical facility, where doctor Robert "Robo" Thompson said he believed the sickness was linked to "alcohol withdrawal".

Marks told him it was 38 hours since he last drank.

Marks shuttled back and forth between his room and BioMed. At one stage, Thompson drew blood from Marks' right arm, later saying that he noted two other needles marks already there.

Marks returned to BioMed for oxygen and valium: "Rodney was very agitated," Wolter said.

"He could not lie still... [and] was breathing heavily." By 3pm, Marks was back in BioMed.

Evidence would later be given that an automatic medical analyser, the Ektachem machine, could have found signs in Marks' blood of methanol poisoning - but it was not working.

Without clues to his illness, Marks faded.

Wolter: "I thought he was getting better. His pupils were huge. They got smaller. He squeezed my hand. He tried to sit up. He then quit breathing and we tried CPR."

Alarms blared across the base, summoning base staff trained in emergency respiration. They tried for 45 minutes to bring Marks back to life, without success.

When Grant Wormald began investigating, there was little to go on.

He had Sage's autopsy report and a handful of interviews carried out before any questions were raised around Marks' death. Those interviews offered few clues - they simply described Marks' final hours and the efforts made to keep him alive.

Wormald needed witnesses, but was unable to compel co-operation. The United States Department of Justice made it clear that the coronial inquest was considered an "informal" inquiry in the department's view, and Wormald would have to contact the science foundation directly and ask for whatever help it was willing to give.

Years later, he would give evidence in court that there was very little help, and that what help there was came slowly. The NSF disputes this: a spokesman says it had co-operated "fully".

Wormald needed witnesses, and asked the NSF to give him access to those who were at the base. It eventually agreed in 2006 to forward a questionnaire to the 49 people Wormald wanted to question - but only after it had approved the questions.

Wormald received just 11 responses. There was no response from some of the more critical witnesses.

Wormald also asked for reports by the NSF into Marks' death and reports into the Ektachem medical computer and was told there were no relevant reports.

The NSF said one inquiry was carried out, but because it was of a medical nature would be "of little value to your inquiry".

The coroner disagreed: medical aspects were "vital" to the inquiry, McElrea said.

Wormald's good police work would later obtain this report - and reveal the existence of others. That report contains the statement that the unexpected death of a 32-year-old "immediately warrants a homicide investigation".

As Wormald continued investigating, apparent pressure was placed on the police through the US State Department. One letter from Wormald records communication from the State Department to New Zealand's Ministry of Foreign Affairs "questioning my perseverance".

In the end, the greatest assistance came from two former NSF staff members who were praised by the coroner for coming forward.

William Silva, who had worked as a base doctor at a nearby station, was able to provide the medical report carried out by the NSF. He was one of those who reviewed Dr Thompson's notes, and was critical of aspects of his practice.

The other was Harry Mahar, who had worked for the NSF in Christchurch as the health and safety officer for the Antarctic programme.

Wormald tracked him down at the State Department in Washington, and in a "candid" conversation (later sworn in an affidavit) Mahar stated there had been a number of inquiries by the NSF into the circumstances around Marks' death.

Along with a medical review, Mahar said lab containers were tested to see if they were correctly marked as methanol and bottles of alcohol were tested to see if there contents matched the labels.

Why the NSF did not offer Wormald the assistance he wanted is a question asked by Marks' family, who were deeply unhappy with the delays.

Marks' father Paul Marks told Science magazine: "If it had been one of yours, a US citizen, I can't believe that the FBI wouldn't have been involved from the start and that no stonewalling would have occurred."

There are those who were there during the winter of Marks' death who tell of drug and alcohol abuse at the station. For such a high-profile and elite agency, these stories could explain the reluctance by the NSF to assist.

The agency has firm rules around this. NSF spokesman Peter West says there was and is a zero-tolerance policy for drug use and the availability and consumption of alcohol is regulated.

Yet evidence produced at the inquest, and interviews with members of that winter's crew, suggest that the policy was not followed. Marks "was known to binge drink alcohol", the inquest heard.

When his room was cleared, there were 18 bottles of liquor in it even though there was alcohol for the taking at the nearby bar.

Silva described him as having a "high tolerance" for alcohol: "I suspected some degree of alcoholism based in a large part on his ability to do well at poker by drinking his mates under the table."

Members of that winter crew told the Herald on Sunday of marijuana being grown at the base. This is supported by testimony at the inquest: one person reported finding a stash of cannabis and base manager Scott Hulse said he smelled marijuana being smoked while walking outside the base.

Hulse came to believe it was being grown somewhere on the base and suspected plants were hidden in air ducts.

Hulse said he was criticised for being heavy-handed, but that it was necessary because of "pretty severe alcohol abuse problems".

Wolter, Marks' fiancee, wrote on her blog "there is an unbelievable amount of alcohol down here".

She added: "I'm not aware of any AA meetings taking place, although it wouldn't be a bad idea for quite a few people here."

When questioned by police after Marks' death over the needle marks in his arm, "she said she knew of people smoking cannabis at the base" but knew nothing of harder drugs.

Along with the alcohol shipped in, there were those on the base who made "Toast Juice".

In Antarctic parlance, "toastiness" is a condition brought on by spending the winter at South Pole, marked by a short attention span, poor memory and irritability.

Toast Juice, which was considered [and discounted as] one possible source of the methanol, was brewed on site. When Wormald obtained a bottle for ESR testing, it was found to be 71 per cent pure alcohol.

Police also probed drug use in the questionnaire sent out. The interest hinged on the single statement given by "Robo" Thompson before Marks' cause of death became known. All further attempts to contact the doctor failed.

In that single statement, Thompson said Marks disclosed intravenous drug use.

According to Thompson, the instances were in the "distant" past, with the exception of a party in Christchurch before coming to the Pole.

It was also Thompson's testimony that Marks - who was right-handed - had two needle marks on his right arm when brought into BioMed on the day he died. Thompson chose this site to draw blood to test, although the Marks family have questioned why Thompson would use the same site.

Wormald also described the decision as "curious".

"Dr Thompson seems to have made little, if any, direct inquisition of Mr Marks in relation to these fresh needle marks," he said.

The autopsy of Marks showed no sign of illicit drugs, only trace amounts of alcohol and a high concentration of methanol."

Evidence presented at the inquest did raise the possibility of intravenous drug use at the base. It was suggested a surviving member of the winter crew, whose name remains suppressed, was using drugs intravenously and offering drugs to others.

In eight years, Wormald learned a lot - but nothing that answered the questions he wanted.

Ask him now about alcohol and drug abuse at the Pole, and he points to the coroner's file.

"What we found out was handed up in evidence." He has become a diplomat.

"The underlying message from my perspective as the investigator was we tried to find out for Rodney's family in the main, and people who might go to Antarctica in the future, what actually occurred.

"I don't know if things have changed but I hope that a good hard look was made at the death and the situation of what transpired down there and it's now a safer place to visit. If nothing else, that's what the family wanted to achieve."

McElrea, in his coroner's report, praised Wormald for what he achieved "given the legal, diplomatic and jurisdictional hurdles" that arose.

With no definite answers, those who knew Marks have taken sides, based on their memories. Schneider says: "I believe Rodney's death was a tragic accident - a terrible mistake on Rodney's part. There is nothing to indicate how he could have made such a mistake and plenty to indicate he should not have made this mistake, and this is what makes his death so difficult to come to terms with."

Harvard professor Dr Antony Stark, who supervised Marks and communicated with him daily, recalls having a routine discussion about lab safety early in his employment.

"It was hardly necessary to do so because he was a professional who was well versed in laboratory techniques and safety."

He dismisses the possibility of suicide.

"Even if he did, I doubt he would have chosen a dose of methanol as the method - it is a terrible, painful death". Neither was it an accident, he says. Drinking a lethal dose during lab work was "essentially impossible".

"It was a terrible death, of someone who was young and full of promise. I don't understand the cause and I don't know if we ever will."