Roswell was a cover-up
One of the first to reach the scene, intelligence officer Jesse Marcel, recognised immediately that it "wasn't anything built by us and it most certainly wasn't any weather balloon". He described finding thin metal strips that he found impossible to bend and strange hieroglyphics; the huge crash site also suggested to him that something other than a balloon just fallen to earth.
Him verdict: Are we really alone? Is it really possible that in the vast expanse of the universe, there are no other living sentient beings? Every star in the night sky is a sun just like our own, many supporting planetary systems not unlike our own. The balance of probability suggests that it is unlikely that we are alone. That does not mean that 'Roswell' is true however - and again requires rather a lot of people to keep quiet about what would be the biggest story in the history of the world - for their entire life
For all the horror of the event itself, and those more than 3,000 deaths, it still seems incredible that so many different aircraft were not intercepted by military jets after losing contact with Air Traffic Control while flying over such sensitive areas as Washington and New York.
A week later a former Pakistani Foreign Secretary, Niaz Naik, told the BBC he had been informed three months prior to the attack that the US was planning a campaign against Afghanistan. The invasion was set for October, by which time public opinion would be softened up by the collapse of the Twin Towers.
In every crime it is interesting to see who gains. The fact that gasoline prices soared in the US within hours may have been just 'gouging' by petrol station owners, but it is hard to avoid the conclusion that US oil interests have been well served by subsequent events in Iraq and the Middle East.
Him verdict: For this theory to stand up, we must conclude that George W Bush is highly competent and intelligent and able to mastermind a complex operation. We must also believe that he was - and is - able to persuade vast numbers of people to keep mum about it, even now he is out of office and powerless. All of these things seem highly unlikely. TE
Climate change is a myth
It is sensible to be suspicious about anything where the most obvious impact is rising prices, and especially as here where the winning side in the climate debate will shape global economic, political and technological developments for decades, even centuries, to come. Temperatures have always fluctuated, so what makes this one so special?
For one thing climate scientists and climate change supporters rely more than on public concern about rising temperatures and the possible effects to fund their research and finance their operations. Many 'authoritative' projections are also known to be based on questionable or discredited methodologies, but are still cited by politicians.
At first we were told that no credible scientists stood outside the consensus. Now we know this to be untrue. Data from apparently respectable institutions has been manipulated, or simply buried. Counter arguments have been ignored or written off as cranky. And requests under the Freedom of Information Act have sent doom-sayers running for cover.
Him verdict: The jury is still out and the story is still running. Many skeptics observe that since the 'weather establishment' can barely forecast accurately what is going to happen the day after tomorrow, we should take their guesstimates about the climate in 20 years time with a considerable grain of salt... On the other hand, even if the climate case is overstated, the supply of carbon-based energy - notably oil - is being depleted now and we shall have to find a plan B eventually, whatever happens to the climate.
The moon landing was a hoax
Forty years on it is one of the great moments of human, scientific and televisual history, yet for many the 'giant leap' simply never took place. Against a background of the Cold War one can see why America might have decided to cheat - and some unanswered questions suggest that maybe they did. This first photo is of a rehearsal in January 1969.
In all the official photographs from the Moon the stars-and-stripes appears to flutter, even though there is no wind on the moon. There is also a question as to whether conventional film in a barely modified Hasselblad could even survive the temperature on the moon, ranging from -233˚C at night to more than +120˚C in full glare.
The same pictures similarly show shadows cast on the moon's surface in several different directions, suggesting there were multiple light sources (as one might find in a TV studio). Finally, none of the photographs show a single star in the sky despite the clarity afforded by high quality equipment and a lack of atmosphere. Was it all a ruse to distract the nation from the ongoing disaster in Vietnam?
Him verdict: This conspiracy would require a truly enormous number of people to keep mum about it to the end of their days; we should have had at least a few deathbed confessions by now about this 41-year-old event. In any case, landing on the moon isn't *that* difficult is it - even in 1969?
Roosevelt welcomed Pearl Harbor
A shattering blow which made the US entry into the war inevitable, the Japanese attack was a major turning point in 20th century history. It has been suggested that Churchill and Roosevelt ('FDR') knew it was coming, and certainly the US Navy Secretary Knox could not have issued a more strongly worded warning.
Knox advised "that precautionary measures be taken to protect Pearl Harbour against surprise attack", but none was. On December 7 1941 hundreds of aircraft and midget submarines of the Imperial Japanese Navy attacked the lightly defended base, sinking nine ships and damaging 21 with the loss of 2,400 American lives.
By cutting off oil supplies to the militaristic government of an expansionist state ,FDR would have known he was courting danger. The President was keen to curtail German dominance, but aware of anti-war feeling at home, and Pearl Harboor enabled him to secure Congressional approval for war which he otherwise might not have had.
Him verdict: The motivation is all there, but there remains a lack of hard evidence. Cunning though he may have been, FDR is unlikely to have wished the deaths of potentially thousands of Americans for this. More likely he simply underestimated the resolve of an aggressive government, running a small island with a large population and virtually no natural resources of its own, who had looked on as western countries had colonised so many countries in the western pacific.
The real question is what on earth possessed Hitler to then declare war on America - thus unnecessarily bringing the whole might of American arms down on him. The night after the attack, Churchill wrote "I went to bed and slept the sleep of the saved and thankful."
The credit crunch was deliberately engineered
When the big losers are you and me, and the apparent perpetrators seem to be carrying on as before, the conspiracy bandwagon cannot help but go on a roll. Now we can all see that bankers are not quite as smart as they supposed - but neither are they quite as stupid as we might think.
We watched them give mortgages to people even we knew could never repay them. But theirs was a longer game: a realisation that when economies collapse and governments step in, all they can do is borrow money. Money which is in private hands, their hands, and which can now be lent at even higher rates of interest.
Of course a couple of banks have closed, and this year's bonuses may be smaller than last. But how many bankers lost their jobs? And how many times have you heard the argument (from the banks) that the only thing that can save us from further financial meltdown is the very industry that caused it?
Him verdict: Not sure about this one. Certainly plenty of bankers made a lot of money 'shorting' the various stockmarkets as they came down. But these were usually the clever ones who realized that lending money to people too poor to pay it back was a plan likely to come unstuck sooner or later, and not the daft folk who lent it out in the first place.
Princess Diana's death
The theory goes that the Security Services murdered the Princess while acting on the orders of 'establishment figures'. The latter's alleged motives were Diana's rumoured pregnancy with Dodi Fayed's child and imminent engagement, and no-one at the Palace wanting the future king's mother to be married to a Muslim.
Unsurprisingly Prince Charles denied there was 'a shred of evidence' for any of this. Yet the Daily Mail subsequently confirmed that two MI6 officers were operating from the British Embassy immediately before Diana's death, and suggested the RAF jet in which Tony Blair went to meet her body was standing-by two days previously.
Even more tantalising, perhaps, is the brief, nine-line note seen by journalists and purporting to come from within the CIA. Naming two men it advised the recipient, 'if you are brave enough, dig deeper to learn about them. Both MI6. Both were involved at the highest level in the murder of the Princess.'
Him verdict: Killing someone by car crash is a notoriously hit-and-miss affair. Indeed, one occupant - bodyguard Trevor Rees-Jones - survived, but amnesia means he can't add much to what is already known. However, the continued mystery of the totally untraced Fiat Uno against which the Mercedes brushed just before crashing is the extraordinary and notable feature of this case, and perhaps rightly is central to the conspiracy theorists' case
Who shot JFK?
A whodunnit to rival Jack the Ripper, the events of November 1963 featured a suspect conveniently murdered before he could go on trial and a popular but flawed and controversial victim who was arguably as likely to be bumped off by the mafia or CIA as by any powerful Cold War rival.
Lee Harvey Oswald (above, after his arrest) reportedly lacked the intelligence to be part of a wider conspiracy. In which case it seems right to ask, did he have what it takes to pull it off himself? Several witnesses also reported the presence of a second gunman on the famous 'grassy knoll'.
The Warren Commission nevertheless insisted all three shots had come from a lone gunman in the Texas School Book Depository (where Oswald worked). Yet reviewing the evidence in 1976-9, the US House of Representatives Select Committee on Assassinations described four shots, saying Kennedy probably died as the result of a conspiracy. Jack Ruby (above) killed Oswald the day after JFK was assassinated.
Him verdict: Oswald was a communist, he had spent two years living in Russia and didn't like JFK being nasty to Castro's Cuba. He was also an officially ranked marksman during his time in the US Army. He had the motive and the skills, and had tried to murder a right-wing US Army general a few months earlier. Finally, as with the moon landing, most versions of this particular conspiracy theory require a large number of people to stay mum for the rest of their days.
‘Lucky’ Lucan: alive and well and living in Luton
It is more than 35 years since the 7th Earl of Lucan vanished after allegedly bludgeoning the family nanny to death in Belgravia, but barely a year passes without him being supposedly spotted somewhere peculiar or a newspaper printing an impression of how the high-rolling gambler might look now.
Billionaire chum James Goldsmith had the resources to spirit him out of the country. Another, casino and zoo owner John Aspinall, made no bones about helping a friend in need if called on so to do. And more recently his own son insisted he did not do it, blaming a burglary which got tragically out of hand. The above is what he would have looked like in 1994; today Lucan would be 75.
But otherwise it is the lack of a body which keeps the rumour mills grinding. Aspinall suggested he drowned off Newhaven, but no corpse was ever washed up. Nor is there anything about Lucan's character to suggest he could organise his own disappearance quite so well at short notice - or indeed survive without the society he craved. His wife is pictured above.
Him verdict: Lucan was certainly well connected and there is no doubt that among the upper classes there is a certain public school all-stick-togetherness that will excuse anything - even bludgeoning the nanny to death. Many believe that Lucan's close pals Goldsmith and Aspinall ( knew more about the case than they let on, but if so they have both taken their secrets to the grave.
Marilyn Monroe was murdered
It remains one of the most compelling, and enduring, Hollywood mysteries. Early in August 1962, Marilyn Monroe was found naked, face down on the bed and dead, aged just 36. The autopsy suggested acute barbiturate poisoning - she was a known long term user - with psychiatric investigators calling it a probable suicide. Many pills were found at the scene, above.
The first LAPD officer to arrive at the house thought otherwise, however, so too did ex-husband Joe DiMaggio. Then, two decades later, when the case was reopened, the LA County District Attorney's office found several 'factual discrepancies' and 'unanswered questions' in the original report - but declined to launch a criminal investigation.
JFK's emotionally unstable lover, and possibly his brother Robert's too, Marilyn was a liability whose house was being bugged just weeks before her death. A close friendship with Frank Sinatra (above right) provided a link with organised crime, a link which could quickly have turned deadly if it looked like she was about to start spilling beans.
Him verdict: We are not sure the motive really stands up on this one. A Hollywood starlet has liaisons with other famous people, some of whom are married? You don't say... That went on a lot back then - still does in fact - but the difference is that then it was largely unreported because of a very compliant, uncompetitive press.
Did she learn great secrets between the sheets? Maybe, maybe not. But what is known is that she consumed a large number and variety of powerful prescription and non-prescription drugs. Habits like this sadly continue to kill famous people with access to obliging private doctors to this day.