Washington DC - Conspiracy theories about the assassination of President John F. Kennedy have floated around the fringes of US politics for decades. Now, his nephew Robert F. Kennedy Jr. could bring them into the heart of the White House.

Kennedy – the vaccine skeptic tapped by President-elect Donald Trump as his health secretary – has been pushing for his daughter-in-law to be the deputy director of the CIA, US media reports say.

Axios said that part of Kennedy's motivation for getting Amaryllis Fox Kennedy the job was to prove his belief that the intelligence agency had a role in the shooting of his uncle in Dallas in November 1963.

It's a move that has reportedly angered some US lawmakers – but which also shows the extraordinary influence that the man dubbed RFK Jr. already has in Trump's transition team.

Marjorie Taylor Greene Marjorie Taylor Greene repeats claim that Democrats are "pedophiles" over Biden's clemency grant

As with his views on vaccines, autism, Covid-19, and fluoride in water, Kennedy's ideas about the assassination are far from the mainstream.

In a radio interview in 2023, RFK Jr. said there was "overwhelming evidence the CIA was involved" in JFK's murder, adding that it was "beyond a reasonable doubt at this point."

That runs counter to the findings of the Warren Commission that investigated the shooting, which found it was carried out by a former Marine sharpshooter, Lee Harvey Oswald, acting alone.

Kennedy said in the same interview that there was "very convincing" but "circumstantial" evidence the agency was also behind the 1968 assassination of his own father, Robert F. Kennedy, who was killed while campaigning for the Democratic nomination for president.

Palestinian immigrant Sirhan Sirhan, who was seized immediately at the scene of the shooting, was convicted of the killing and remains in jail.

But a belief in conspiracy theories has never been a bar to a job with Trump, the great disruptor of US politics.

Indeed, in RFK Jr.'s case, Trump appears to have embraced it.

The former environmental lawyer made his own White House run as an independent earlier this year before throwing his support behind Trump.

Donald Trump Trump reportedly plans to toss policy blocking ICE arrests at schools and churches

Trump rewarded him by nominating him for his dream job as Health and Human Services secretary – although Kennedy faces potentially rocky confirmation hearings.

Since then, Kennedy has become one of Trump's key courtiers.

After the November 5 election, he was photographed on Trump's plane eating a McDonald's meal with tech tycoon Elon Musk and Trump's son Don Jr. – despite Kennedy's own campaign against junk food.

RFK Jr. was at Trump's side again on Thursday as the president-elect rang the New York Stock Exchange bell to celebrate being named Time magazine's Person of the Year for a second time.

Asked by Time what he would do if RFK Jr. moved to end childhood vaccination programs in the US, Trump said he would be having a "big discussion" with Kennedy.

The New York Times reported on Friday that the lawyer helping Kennedy pick officials for the Trump administration had previously petitioned US regulators to revoke approval for the polio vaccine, which scientists say has saved more than a million lives and prevented perhaps 20 million cases of childhood paralysis.

With Trump now reportedly considering Amaryllis Fox Kennedy for the CIA job, it seems Kennedy's other left-field theories could also get a major airing.

Trump himself has promised to release the last of the previously classified files on the Kennedy assassination that are held in the US National Archives.

The appointment of Fox Kennedy – who is married to RFK Jr.'s son and served as her father-in-law's campaign manager – would be controversial for other reasons, too.

In 2019, she published a memoir about her time in the CIA but reportedly did not seek advance clearance from the government.

Fox Kennedy hit back at reports that some lawmakers and former intelligence officials oppose her getting the role.

"A Kennedy at CIA, they fret," she wrote on X. "A DJT [Donald J. Trump] loyalist at Langley, they wail. She must be stopped at all costs!"

For America's most famous – and tragic – political dynasty, Robert F. Kennedy Jr. has become a black sheep.

JFK's only grandson, Jack Schlossberg, accused RFK Jr. on X this week of being "so obviously a Russian spy" after the reports about his daughter-in-law.

Kennedy's office did not reply to a request for comment.