Last week on SkepticBlog Michael Shermer wrote a nice post about JFK assassination conspiracies, and not surprisingly a couple of conspiracy advocates showed up in the comments. While reading through their arguments I was struck by how consistent the tactics and tone of conspiracy theorists tends to be. They are heavy on sarcasm, ridicule, and condescension, and like to call anyone who disagrees with them “gullible.”

It also struck me that skeptics can often take a similar tone, and certainly conspiracy theorists (as with deniers) think of themselves as being the true skeptics. But they are skeptics’ evil twins – they use a tone that only the harsher skeptics use, and only when dealing with the truly absurd – those topics that we do not wish to legitimize with serious treatment, but don’t wish to ignore either. Some claims deserve ridicule, and anything less falsely elevates them.

It is true that sometimes skeptics do not properly adjust their tone when dealing with topics that range from the truly absurd to the genuinely controversial. I do think it is counterproductive and unfair to attack a well-meaning and generally scientific individual with whom you happen to disagree about a complex and controversial topic, as if they were a homeopath or creationist. This is a minor problem, for example, with the show Bullshit. Penn and Teller have created a premise for their show that does not lend itself to a nuanced discussion of a scientific controversy – and so they end up giving circumcision and second-hand smoke the same treatment as magnet therapy and feng sui.

It is instructive, in my opinion, for skeptics to read conspiracy theorists because they are an excellent example of exactly how not to behave. Of course, their tone is all the worse when used to defend a pseudoscientific position, and attack the position that is most supported by logic and evidence.

JFK Conspiracies

It is not my intent to do anything like a thorough treatment of JFK conspiracies – books have literally been written examining this historical event in painstaking detail. As many have in the comments of Shermer’s article, I highly recommend Case Closed by Gerald Posner. Posner’s book is painstakingly researched – he actually itemized the Warren commission records, doing a service to future researchers. He also did what conspiracy theorists often neglect to do – take a close look at the prime suspect, Lee Harvey Oswald. Posner builds a compelling case that Oswald was indeed a lone nut and the lone shooter at Dealey Plaza.

Commenter “Joe” uses a “poisoning the well” strategy to dismiss Posner’s impressive work in one stroke, writing:

Furthermore, for all you “Case Closed” freaks, you know that Posner is a recognized plagiarist, right? Why would you trust anything written by such a person?

This is highly unfair, and exactly what I predicted would happen when I first heard of the plagiarism case. Posner and the Daily Beast for which he was writing admit that the five sentences Posner paraphrased from the Miami Herald constitute plagiarism. Posner insists that it was inadvertant – in doing extensive research for an article you make a lot of notes, and apparently he confused copy from the Herald with his own notes and paraphrased them in the final article. Without getting off on too much of a tangent, knowing Posner and his work I am inclined to believe him. No matter how you interpret this episode, however, it does not invalidate the research and arguments that went into Case Closed – that is a childish stance.

JFK conspiracy theorists have also attacked Case Closed, arguing that it is riddled with errors. This is, in fact, true – there are numerous factual errors in the book. It would be remarkable, almost preternatural, if there weren’t. Case Closed is a massive tome chock full of factual information. Errors are always going to creep into such a work. Posner is open about the errors. But the real question is – do any of the errors change the final analysis of the event? Most of the errors are trivial and inconsequential to the real question of whether or not Oswald was the lone assassin. Further, they are a random scatter of minor errors – not a consistent bias in one direction. Posner reports that he went into this project thinking that he would uncover the real conspiracy, but his research led him to Oswald as the lone shooter.

The Head Shot

Commenter Sunny raises the old canard made famous on Oliver Stone’s JFK movie – “back and to the left, back and to the left.” How could Kennedy’s head move back and to the left if he were shot from behind? Doesn’t this prove a shooter in front and to the right of the president? Well, no. This argument gets filed under the conspiracy theorist strategy of making naive assumptions about what should have happened, and then anomaly hunting for anything that does not fit the naive assumption. We see this, for example, with those who think they know what the debris field in front of the Pentagon should have looked like on 9/11.

When I made the point that the physics actually supports a single bullet from behind, Sunny wrote:

As for the bullet causing JFK’s head to be pushed towards the bullet I can only say YOU HAVE TO BE KIDDING!!! Perhaps I overestimated the people on this blog. I thought you had a science background…

The head shot has been analyzed by numerous individuals, and the physics makes perfect sense. I wrote about it extensively here, but quickly – the bullet entered the back of JFK’s head and exited in the right temporal area, essentially taking off part of the temporal bone. JFK’s brains, compressed by the inertia of the bullet, then sprayed out of this hole in the skull – spraying up and to the right, pushing JFK’s head back and to the left. I actually linked to a conspiracy site that has a good slow-motion close up version of the Zapruder film at the moment of the head shot. Look closely at the video – JFK’s head first moves forward when the bullet impacts, then you can actually see the spray of blood and brain going forward and pushing his head back. Here is a good analysis by a neurosurgeon. When examined closely, you can actually see on the Zapruder film a spray of brain and fluids shoot up 30 feet above JFK’s head.

Sunny, however, replaces careful analysis by scientists with an all-caps ridicule of the scientific background of those who disagree with him.

The Magic Bullet

The very name, “magic bullet,” speaks to the fact that this argument against the standard interpretation of the JFK assassination is a massive straw man argument. There is nothing “magical” about the second bullet fired by Oswald. It is likely that Oswald’s first bullet missed. His second bullet (the alleged “magic” bullet”) hit Kennedy in the back of the neck, then struck Connally in the back, wen through to the front, hit off his wrist then lodged superficially in his right thigh. This bullet was later recovered from Connally’s stretcher.

Conspiracy theorists love to ridicule the “single bullet theory” as if their ridicule is a substitute for careful analysis. Sunny writes:

But the magic bullet, the one that changed direction four different times and gained weight (lead) in the process. The bullet left lead in the bodies but when weighed had not lost that much lead. Go figure! More magic then we thought.

The trajectory of this bullet has been analyzed by multiple different teams, an every important aspect has either been replicated or supported by evidence. This page has a summary of links, various analyses indicating that the relative positions of JFK and Connally, with respect to each other and Oswald’s sniper’s nest, make for a straight trajectory, with a slight downward deflection from passing through Connally’s chest. It did not have to change direction four times.

Then there is the question of the condition of the bullet recovered from Connally’s stretcher, about which Sunny writes:

Then there is the bullet, in perfect condition, that magically (no can’t use that word, mysteriously) appeared on the stretcher at the hospital. This magical, oops, mysterious bullet was indeed fired from Oswalds gun ( the gun they claimed Oswald owned) but it was also just as clearly never fired at a body because it was captured in pristine condition. Clearly this bullet was planted for the purpose of implicating Oswald. So we have two Magic bullets.

The bullet, in fact, was not in “perfect” or “pristine” condition, although this claim is often repeated. Here is a picture of the bullet in cross section – showing significant flattening. This is hardly pristine. Further, this has been replicated (here also)- a similar bullet fired from the same kind of gun hitting a bone at the same speed results in similar flattening.

Sunny also repeats the claim that the total weight of lead found exceeded that of the original bullet. But this is simply not true:

“Some critics have contended that the four bullet fragments in Governor Connally are too many to be accounted for by the two grains of lead missing from bullet 399. In our experiments we were able to make forty-one such fragments from the two-grain piece of lead that extruded from our test bullet. It can safely be said, therefore, that four fragments are by no means too many to be accounted for by the two grains missing from bullet 399.” — John K. Lattimer; Pages 276-277 of “Kennedy And Lincoln”

Burden of Proof

Perhaps the primary strategy of the conspiracy theorist is to make a demand for proof to an arbitrary level of certainty (meaning whatever evidence is available will never be enough), and then declare the failure to meet their arbitrary demands indicates that their alternate conspiracy theory wins by default. Sound familiar? – this is the same strategy as denialists, such as creationists.

For example, Sunny writes about the single-bullet theory:

Its defenders have spent a lot of time proving that it could have happened that way, which is not the same as proving that it did, a distinction they don’t make.

This is a straw man. Conspiracy theorists spend a great deal of time arguing that the single bullet could not have caused JFK’s and Connally’s wounds. In response, conspiracy skeptics have demonstrated that the conspiracy theorists are incorrect in their analysis, and the single bullet could have caused the wounds. To this conspiracy theorists respond – “yeah, but that doesn’t prove it actually did happen.” They then pretend that the confusion of “could” and “did” is the skeptics’, and not theirs.

This is reminiscent of creationists who argue that evolution (or some particular aspect of it) could not happen. Biologists then respond by showing that evolution could happen, to which the creationist respond – “yeah, but that doesn’t prove it actually did happen.”

Both conspiracy theorists and creationists miss the point – proving plausibility counters arguments of impossibility. But just as with evolution, there is plenty of evidence that the single bullet, and in fact the entire shooting, did in fact occur as the accepted story stated – three bullets fired by Oswald from the sniper’s nest.

Commenter Joe writes:

Despite your insistence, NO ONE has ever exactly replicated what SBT adherents claim. There is always one or more missing or fudged elements, or some adjustment made or assumed in order to produce the preconceived results.

This is a good example of setting an arbitrarily high bar for evidence, then claiming the conspiracy theory wins by default. Experimenters have replicated every key aspect of the shooting. Analysis of the Zapruder film and other evidence is also consistent with Oswald as a lone shooter. But it is unreasonable to expect that someone can replicate the shooting in every detail. There is always a bit of chaos involved in such high-energy events. Some shots you just can’t make twice. That doesn’t disprove the single bullet theory.

Also, Joe is taking the wrong approach. Like creationists, he is trying to set up a false dichotomy – if there are flaws in the standard theory, then conspiracy theories win by default. Then all he has to do is shoot holes in the standard theory and make unreasonable demands for proof. (Again – shades of creationism).

A more rational approach, however, is to consider all competing theories and see which one the evidence fits best. The evidence fits the single shooter theory. There is no specific conspiracy theory for which there is any direct or compelling evidence. Conspiracy theorists resort to anecdotal and circumstantial evidence. They nitpick away at the solid evidence for Oswald, and then put in its place the flimsy evidence for their pet conspiracy.

There is no hard or compelling evidence for the presence of additional shooters in Dealy Plaza. No extra bullets have ever been recovered (how did the alleged additional shooters ensure that their bullets would not end up in someone’s body or the car?).

Conclusion

I cannot do justice to the volume of evidence for this complex historical event in a single blog post. My purpose here is to expose the style of logic and argument employed by conspiracy theory advocates. Their style is remarkably consistent. Further, they employ many of the same strategies as denialists.

While they try to wear the mantle of skeptics, their methods are not truly skeptical. Conspiracy thinking is pseudoskepticism. It is, however, a good object lesson for skeptics – a reminder of the need for humility in addressing complex topics.