The life of Robert F. Kennedy Jr took an odd turn in 2005. Possibly because of his own son’s nut allergy or possibly because, as he would later say, other parents had been approaching him with concerns, he became worried that vaccines might be the cause of a spike in childhood neurological disorders.

This was not new territory. The British doctor Andrew Wakefield had already made waves in 1998 for his claims that the MMR (combined measles) vaccine was linked to a rise in autism cases. He was subsequently found to have fraudulently falsified his research and was banned from practising medicine.

But the notion that some vaccines were a danger that was being covered up by “the establishment” was conspiracy catnip for Kennedy, nephew of president John F. Kennedy (JFK) and son of former United States attorney-general Robert F. Kennedy.

RFK Jr, who until that point had a storied record as an environmental lawyer, dived into the topic with zeal, sharing his findings in Rolling Stone and on the website Salon. “I devoted time to study this issue because I believe that this is a moral crisis that must be addressed,” he wrote, quoting one activist as telling him: “The damage caused by vaccine exposure is massive. It’s bigger than asbestos, bigger than tobacco, bigger than anything you’ve ever seen.” His research, though, was problematic, and the story had to be corrected several times after publication. It was later disavowed entirely.

But the die was cast. Kennedy shrugged off the criticisms and doubled down on his vaccination theories, which helped propel him, nearly 20 years later, to run for president of the United States. His constituents are a curious coalition of anti-vaxxers, Bitcoin evangelists, libertarians, disaffected Democrats, manosphere podcasters and those old enough to still remember, misty-eyed, the golden years of the Kennedy family’s “Camelot”.

Dismissed by some as a no-chance crank when he announced his campaign in 2023, RFK Jr had been polling strongly enough to be taken seriously, with around 12 per cent of the popular vote in May, which had dropped to 4.2 per cent in 26 polls after Kamala Harris entered the race in August: still not nothing. If he sticks around until polling day, there’s an outside chance he could sway the result in a close race towards Harris or Trump. Which is why his opponents have been paying attention.

And sometimes it’s hard not to. Most recently, there has been the incident involving the bicycle and the bear. RFK Jr said in a video, posted on social media in August, that in an episode of high-jinks in 2014 he dumped a dead bear cub in New York’s Central Park and staged it to look like a bike had hit it. In the video, he explains he had been driving in the Hudson Valley when a woman in a van in front of him had hit and killed the cub, which he then put in the back of his car, intending to skin it and store its meat. But he had been out hawking (hunting game using a hawk), then had a late dinner then had to go to the airport.

“At that time, this was the little bit of the redneck in me,” he tells comedian Roseanne Barr in the video. “I wasn’t drinking, of course, but people were drinking with me who thought this was a good idea,” he says. “I had an old bike in my car that somebody asked me to get rid of. I said, ‘Let’s go put the bear in Central Park and we’ll make it look like he got hit by a bike.’” The discovery of the bear’s body sparked a police investigation. In the video, RFK Jr explains that fact-checkers at The New Yorker had asked him about the incident ahead of the publication of a story about him. “Looking forward to seeing how you spin this one, @NewYorker…” he wrote with the video post.

If this sounds unusual, consider another story that came to light this year, about a particular health struggle of RFK Jr: he said he had, at one point, suffered some memory loss due to a dead parasitic worm being found in his brain.

So who, exactly, is Robert Francis Kennedy Jr? Why is he running for president? And why are the major parties so concerned?

Who is RFK Jr?

“The Kennedys, for a long time but not any more, per se, were considered the royal family of the United States,” explains Thomas Whalen, a presidential historian at Boston University. RFK Jr is a member of the third generation of the Kennedy dynasty. He was nine when JFK was assassinated in a motorcade in Dallas in 1963, and 14 when his father was shot in a Los Angeles hotel after claiming a win in pursuit of the Democratic presidential nomination in 1968.

“He was in the hospital after his uncle had been shot, and at 14, he was a pallbearer for his father,” says David Nasaw, an emeritus professor at the City University of New York, who has interviewed several Kennedys including RFK Jr. “From that point on, he lived the most troubled life.”

RFK Jr veered into drug addiction in his teens and 20s, and was eventually sentenced to two years probation for possessing heroin after he fell ill in an aeroplane toilet in 1983. To satisfy the conditions of his probation, he volunteered for the environmental activist group the Natural Resources Defence Council, a turning point.

“We talked about [the addiction episode] at some length,” says Dick Russell, a long-time friend of Kennedy and author of the recent biography The Real RFK Jr: Trials of a Truth Warrior. “He felt that this was, you know, a struggle that had really shaped his life in the sense that he was able to recover and become an environmental lawyer. He was somebody who had been through a lot of tough times. And he had been able to not just maintain himself but become a stronger person.”

In 1995, New York Magazine called him “The Kennedy Who Matters” amid a push to protect the city’s water supply. In 1999, Time named him a “hero of the planet” for his work at the not-for-profit Riverkeeper. Career highs included cleaning up the notoriously polluted Hudson River; a battle to close the nuclear power plant Indian Point; and work to defeat dams in Chile and Peru. He spent a month in prison in 2001 for protesting against US naval exercises on a Puerto Rican island; in 2013, he was arrested and fined in Washington, DC, with one of his seven children, son Conor, while rallying against the extension of an oil pipeline between Canada and the US.

His early career in public life fits a well-trodden path in the Kennedy family. His grandfather, Joseph P. Kennedy – an investor whom Fortune placed in the top 16 wealthiest US individuals in 1957 – was US ambassador to Britain and intended for his fortune to enable his family to pursue public life. Ted Kennedy, another of RFK Jr’s uncles, was elected to the Senate nine times. His aunt, Eunice Kennedy Shriver, founded the Special Olympics. “None of them went into business or tried to make money,” Nasaw tells us. “It was mostly the same with the next generation, the grandchildren.”

Some of the Kennedys in public service

Of RFK Jr’s 10 siblings, two have entered politics. His cousin, Caroline Kennedy, is the US ambassador to Australia. Meanwhile, the Kennedy family connection with what used to be called “the jet set” endures (think Marylin Monroe; Jackie Kennedy-Onassis). RFK Jr is married for the third time, to actress Cheryl Hines, who played the wife of Larry David in the TV comedy series Curb Your Enthusiasm. Son Conor briefly dated Taylor Swift. In RFK Jr’s home office in Los Angeles, he reportedly has a stuffed tiger (a gift to his father from Sukarno, the first president of Indonesia) and a stuffed bat from the actress Glenn Close, godmother to one of his two daughters.

“He has been brought up as a Kennedy to believe in himself,” says Nasaw, “to believe that he’s the smartest, most charming man in any room.” But there is also something different – a tendency to view events through the prism of conspiracy and corruption. “He has this brooding intensity.”

When he visited RFK Jr for an interview in the early 2000s, Nasaw was impressed. “I didn’t sense anything out of the ordinary,” he says. Then Kennedy gave Nasaw a book to read. He was surprised to later find it was a “super-conspiracy theory” that blamed the CIA and US Defence Department for JFK’s assassination. “I’m a historian, and I know all this literature backwards and forwards, and I’d never heard of this book,” Nasaw says. “It was more outlandish than anything I’d read.” Nasaw says this is a worrying mix. “There’s a hubris and egotism that’s taking him beyond bounds.”

What does RFK Jr believe?

RFK Jr was born into a family at the centre the biggest conspiracy theory in US history – that JFK’s assassin, Lee Harvey Oswald, wasn’t acting alone. That there was a “second shooter” that day in Texas, that JFK was killed by the Mafia, or the CIA, or both. “That’s the first conspiracy that this young boy has to confront,” says Nasaw, who believes the swirling theories and distrust of official findings impacted his worldview. “If there was ever a young man, a human being, who was destined to get into trouble and see the world as one giant conspiracy, it was Robert Kennedy Jr.”

His scepticism and distrust of “official stories” initially found an outlet in environmental work as he took on corporations and regulators, inspired, he has said, by the work of Rachel Carson, whose 1962 treatise Silent Spring warned America of the dangers of the insecticide DDT. “If Kennedy had stuck to environmentalism, he might have achieved the ‘heroic role’ he craved as a child,” writes Andrew Miller in The Economist. “But the instinct had a logic and momentum of its own.”

Indeed, he was universally well regarded until he delved into vaccination science, says his biographer, Dick Russell. “People that had been supporting him all along suddenly decided not to because they felt like he was overstepping his bounds.” He has subsequently made remarks or raised questions about 5G networks being used for mass surveillance and to control behaviour, antidepressants playing a role in rising school shootings, that Republicans “stole” the 2004 presidential election, that Wi-Fi “opens your blood-brain barrier”, and that chemicals in water play a role in transgender identity. He says, however, that he is not an “anti-vaxxer” but has concerns over the way some vaccines are manufactured.

In 2018, he went to see Sirhan Sirhan, the man convicted of killing his father, at the Richard J. Donovan Correctional Facility, a California state prison outside San Diego. After that meeting, he called for the investigation to be reopened. (RFK Sr’s widow, Ethel, and most of his children have opposed Sirhan’s release.)

While RFK Jr’s most notable passion is to link childhood vaccines to autism – a claim the US Centres for Disease Control and Prevention has debunked – he was turbocharged during the COVID-19 pandemic, calling mandatory vaccination policies “a crime against humanity”.

He founded the group Children’s Health Defence, which claims it provides a “counterview backed up by facts that the status quo doesn’t want you to know”. The group has been removed from Facebook and Instagram for sharing misinformation. He sold more than a million copies of a 2021 book claiming former US chief medical adviser Anthony Fauci, billionaire Bill Gates and others formed an alliance to exercise control over global health policy.

Kennedy’s unusual strained voice (he has a vocal condition called spasmodic dysphonia) and twinkly eyed resemblance to his father and uncle lend authenticity to his often quixotic ramblings: he may not entirely make sense, but he sounds like he might. “The same way my uncle discovered television in 1960 and realised it was going to be a new path to the White House, podcasts are a good media for me,” he told Vanity Fair.

His views have caused a rift with family members. In 2023, his sister Kerry Kennedy, president of the Robert F. Kennedy Centre for Justice and Human Rights, responded to one of her brother’s suggestions that there was an argument COVID-19 was an ethnically targeted bioweapon. “I strongly condemn my brother’s deplorable and untruthful remarks,” she said. His nephew, Joe Kennedy III, a former congressman and now special economic envoy to Northern Ireland, called the comments “hurtful and wrong”.

Why is he running for president now?

Ask Kennedy why he wants to be in the mix come the presidential election in November, and he responds with “typical ‘third party’ stuff”, says Associate Professor Zim Nwokora at Deakin University. That is, the major parties are failing America, and his sense of duty to the nation is forcing him to offer an alternative.

As Kennedy told CNN in April, “My supporters are people who aren’t going to vote at all. My donors are people who had given up on the American political process and are re-engaging because they don’t want to choose between the lesser of two evils.” Whoever gets elected will be able to make changes only around the margins, he said, “taxes or abortion or whatever”. He had a much bigger mission: “The chance for me to actually change the nature of governance in our country.”

RFK Jr seems to believe that it is his destiny, as a Kennedy, to sit in the White House. “From my youngest days, I always had the feeling that we were all involved in some great crusade,” he once wrote, “that the world was a battleground for good and evil … It would be my good fortune if I could play an important or heroic role.”

‘He’s continuing the work of his father, Robert F. Kennedy, a man that we think of as one of the great moralists. And it’s that moralism, on a different set of issues, of course, that is propelling him into this race.’

Speaking to us from Los Angeles, Dick Russell calls it “a divine force, you know, that’s helping guide him”. Russell was close to finishing the biography when Kennedy suddenly decided he would take a tilt at the presidency. “He was really doing a lot of soul-searching about it. And he felt like the country was so divided, like they’ve never been since the Civil War, and that he didn’t see anybody out there who could heal the divide. He was not in this to be a spoiler, as he’s been called. He really feels like he’s the guy who can, you know, appeal to enough people to try to bring the country together.”

Tim Lynch, professor of American politics at the University of Melbourne, calls it a sense of “noblesse oblige”, the French-derived philosophy that with privilege comes responsibility. “He’s continuing the work of his father, Robert F. Kennedy, a man that we think of as one of the great moralists. And it’s that moralism, on a different set of issues, of course, that is propelling him into this race.” RFK Sr was particularly admired for campaigning to end child poverty in the US, for championing civil rights and, as attorney general, relentlessly pursuing organised crime.

RFK Jr initially intended to challenge President Joe Biden for the Democratic nomination on Kennedy home turf. “The Kennedys are remarkable for their sense that the whole American experiment hinges on their success,” says Lynch. “That sounds more disparaging than it is, but their sense of self-confidence, that the whole system is engineered around the Kennedy family, that they are required for the republic to prosper, in part explains their success and their durability.”

Yet RFK Jr did not poll particularly well as a potential Democratic candidate and, to be fair, parties have very rarely countenanced opposing a sitting president. So in October 2023, he bailed from the party’s primaries process to run as an independent. “I never intended to run for president,” he said. He “saw things happening to my party and my country that made me frightened about the world that my children are going to grow up in”.

What are his chances?

Thanks to the peculiarities of the US electoral system, RFK Jr’s chances of winning as an independent are slim. Only one candidate has ever managed it, and that was George Washington in the late 1700s. In 1992, independent Ross Perot received nearly 19 per cent of the popular vote nationwide but did not win a single state. So, it’s hard.

The major hurdle is that candidates have to be on the state ballots, a bureaucratic process that’s difficult and expensive without the backing of a major party (long story short: many signatures must be harvested). Kennedy will struggle here but has some wealthy donors to make the process a little easier, including his running mate, 38-year-old Nicole Shanahan, a wealthy Silicon Valley businesswoman who has reportedly already spent millions on the campaign.

‘He receives an inordinate amount of coverage and curiosity because, among the Democrats, there’s still the hope the Kennedy dream might live again.’

“The people who kind of run these kinds of campaigns, often they do think they have a chance to win,” Sydney University and the University of South Alabama’s Thomas Adams tells us from New Orleans. “They do think there’s going to be a ‘come to Jesus’ moment, where people realise how correct they are about vaccines and global warming.”

The Kennedy brand remains a strong factor, says Bruce Wolpe, a Colorado native and a senior fellow at the United States Study Centre at the University of Sydney. “If he was Robert ‘Smith’, people would not be paying attention to him. He receives an inordinate amount of coverage and curiosity because, among the Democrats, there’s still the hope the Kennedy dream might live again.”

Kennedy has also successfully canvassed a hotchpotch of other sympathetic audiences, including vaccine fellow travellers, right-wing podcasters and Bitcoin conventioneers. (He calls the blockchain a “bulwark against totalitarianism” and wants the digital currency to be used for the entire US budget, a move he claims would improve transparency.)

“It’s quite possible he’s just driven by his anti-vaccine pitch, that really what’s behind it is he’s trying to generate a lot more support for the anti-vaccine movement,” says John Hart, a former head of department at the Australian National University and author of The Presidential Branch: From Washington to Clinton.

‘Some of the old rules go out of the window. Things are up for grabs in a way that they haven’t been in the past.’

A decade ago, perhaps, RFK Jr’s fringe views might have seen him immediately dismissed as a serious candidate. Post-Trump, Nwokora is not so sure. “Some of the old rules go out of the window,” he says. “Things are up for grabs in a way that they haven’t been in the past.”

Which side could RFK Jr cause more damage to?

“Significantly more ... RFK Jr voters go for Trump,” says Jared Mondschein from the United States Study Centre, who researches US election polls. The anti-vax movement, in particular, may sway towards RFK Jr and away from Trump. According to The Washington Post, more than six in 10 Republicans “aren’t confident in the safety of the coronavirus vaccines, and large numbers are sceptical of other vaccines as well”.

If it’s a contest between RFK Jr and Trump over “strongman”-style physical ability, Kennedy – who recently posted a video of himself working out with his shirt off – should win hands down. That said, he has not reached his eighth decade entirely unscathed. In 2012, he revealed he had been diagnosed with mercury poisoning from eating too much fish, and that a dead parasitic worm had been found in his brain after scans for a possible brain tumour. “I have cognitive problems, clearly,” he said in a deposition made during divorce proceedings. “I have short-term memory loss, and I have longer-term memory loss that affects me.” The New York Times reports that he says he has since recovered and has suffered no ongoing effects.

Practically, RFK Jr’s path might be smoothed by forming an alliance with another organisation, such as the Libertarian Party, which would have the mechanisms in place to get him spots on more ballots. But that would come with its own complications, says Nwokora. “It means that he becomes bound up with the ideology of that particular party. So that’s a dilemma for him.”

In April, 15 Kennedy family members appeared at a Biden campaign event in Philadelphia to show unequivocal support for the party and the then presidential re-contender, even if they did not explicitly name RFK Jr in their remarks. (“I don’t know anybody in America who has got a family who agrees with them on everything,” RFK Jr told CNN.)

Democrat strategist Lis Smith told The New York Times in May: “Generally, RFK Jr finds support among voters who are dissatisfied with the two-party system, who aren’t enthused by either of the major-party candidates, and who actually gravitate toward him because of his last name … A significant percentage of voters who say they support him don’t know anything about him. Which signals to us that the Kennedy name is extremely powerful in attracting support for him.”

Certainly, his more eclectic views might be attractive to erstwhile Republican voters, says Bruce Wolpe: “People who like Trump policies but don’t like Trump.” Consequently, Trump has recently pivoted from a neutral stand on RFK Jr to attacking him as a Democrat “plant” and a “wasted protest vote”. Ironically, Trump has only himself to blame for clearing the path for an idiosyncratic candidate like RFK Jr. “Trump has opened up the debate,” says Lynch. “The debate is no longer controlled by old-school Democrats and old-school Republicans.” Twenty years ago, he says, Kennedy would have been seen as “nuts”. “But he wouldn’t have been taking these positions because the environment wouldn’t have enabled them.”

Jared Mondschein says RFK Jr can’t be pinned down on a political spectrum. “The far left and the far right now are meeting; that’s why I can’t commit to him being far left or far right.”

There was a mix of views on his chances back in May: “He doesn’t have a chance; his role is a spoiler,” said Mondschein. Said Nwokora: “It’s a theoretical possibility. I wouldn’t consider it anything more than that.” Dick Russell believed RFK Jr’s had “a decent chance” of taking the top job but conceded it would be an uphill battle: “There’s no doubt about it. But I do think that more than any time since I’ve been alive, that this is a possibility.”

This article was first published on May 5 and has since been updated to reflect news events.

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