Every time I heard someone use the term “witch hunt” recently I was reminded of that quote from Indigo Montoya from The Princess Bride – “You keep using that word. I do not think it means what you think it means.” With the recent release of the Mueller report, many news outlets feel obliged to interview people on the street about their opinions. This is an inane practice that provides no useful information, just cherry-picks random opinions. Every single time I heard the term “witch hunt”, it was used incorrectly.

It’s not just random people who do not understand the term. Because Trump has used the term over 260 times and counting to refer to the Mueller probe, many political commentators have also been using the term – mostly incorrectly. Dana Milbank, for example, wrote in the Washington Post:

Just because Trump says something, however, doesn’t automatically mean it’s wrong. The treatment of Trump by special counsel Robert S. Mueller III and other investigators does have characteristics of a witch hunt. This is because Trump has characteristics of a witch.

So says a leading authority on the history of witchcraft, Thomas J. Rushford, history professor at Northern Virginia Community College in Annandale. In an anthropological sense, Trump “is really quintessentially a witch figure,” the professor tells me, and if what is happening to Trump is a witch hunt, “it is only in a good sense, that is, this is society policing the boundaries that they believe to be ethically and morally right.”

But there is no witch hunt “in a good sense.” This misunderstands the essence of what a witch hunt is. The logic here is that if Trump is analogous to a witch, then the investigation was a witch hunt. Or, on the other side, if Trump is innocent of collusion, then by definition the investigation to determine whether or not he is guilty is a witch hunt. One random interviewed person even said that because the probe found no evidence of collusion it was a “failed witch hunt.”

The reason I find all this annoying is that the concept of a witch hunt is extremely important to critical thinking and skepticism. We devote an entire chapter to the idea in our book on skepticism.

So what is a “witch hunt?” The term does derive from literal hunts for witches that consumed Europe for centuries, and famously spread to the colonies in the Salem Witch Trials. The term, however, refers to the methods of investigation that were employed in the literal witch hunts, and that were even codified in the primary guide to hunting witches – the Malleus Maleficarum.

Those methods include: accusation equals guilt, suspension of the normal rules of evidence, allowing “spectral” evidence, methods of investigation constitute punishment, encouraging accusations, and accusations used as a weapon against enemies or rivals. Meanwhile, the farce of a witch hunt masquerades as a legitimate trial.

Implicit in all this is the presumption of guilt, in fact the near guarantee that the accused will be found guilty. The only path to proving one’s innocence requires enduring an outcome as bad or worse than the punishment for being found guilty. We will dunk you under the water, and if you drown you are innocent (but at least you will have a Christian burial).

When Trump accused the Mueller investigation of being a “witch hunt” he was saying that the investigation itself was not legitimate, was not using fair methods, had a predetermined outcome, and was ultimately a farce. It was, in his view, the political version of a witch hunt, a political hit-job meant to destroy an opponent.

So here’s the thing. If Trump were guilty, that would not mean the investigation was a witch hunt that found a real witch – it would mean it wasn’t a witch hunt. (You see – witches don’t really exist. I’m not talking about Wiccans, but the kind that make a pact with Satan and cast spells.)

Apparently the investigation found no evidence of criminal conspiracy (according to Barr’s summary). By definition that means the investigation was not a witch hunt. That doesn’t make it a failed witch hunt, it makes it not a witch hunt. It was a legitimate investigation that used valid and legal methods to uncover evidence related to the charge of the investigation. As long as proper methods were used, and the conclusions fairly flow from the evidence uncovered – it was never a witch hunt.

None of the critics of the Mueller investigation, including the president, provided evidence that any of the features of a witch hunt took place. How were the normal rules of evidence suspended? What kinds of “spectral” evidence were allowed? This refers to evidence that is not material, such as a person having a vision and having their vision accepted as formal evidence in the court. A more modern version of this would be admitting the seeings of a psychic, or allowing for facilitated communication testimony (something which is actually still done on occasion.)

It’s frustrating that Trump’s sloppy use of the term to delegitimize an investigation by his own Justice department has now come into common but wrong use. He has simply confused the public about what is a critically important concept for any democracy or free society. We are all protected by rigorous rules of evidence. The system is far from perfect, but the protections we do have are critical. Actual modern witch hunts degrade these protections, as they did during the McCarthy witch hunts for alleged communist infiltrators, and later during the Satanic Panic of the 1980s, and later still with the many accusations occurring via facilitated communication.

Actual witch hunts are an enduring threat, and we must as a society understand their essence and how to protect against them. That cause is now harmed by the profligate and incorrect use of the term, watering it down to mean any investigation you don’t like or find politically inconvenient. This is an extension of the “fake news” phenomenon, where standards of journalism and evidence become muddied and confused so all claims are portrayed as equally valid and only a matter of tribal affiliation.

That is really the scary part of this. Trump and his followers believe the investigation was an illegitimate witch hunt because they did not like it, or because they believed Trump was innocent – regardless of the methods used, or the professionalism of Mueller and his team.

They are, ironically, now in a difficult position (not that they will recognize this). Trump has delegitimized an investigation that has cleared him of criminal conspiracy (the obstruction of justice part is more complex, so we will leave that aside for now, and I know this also does not mean he did not do anything bad or immoral, just not rising to the level of provable criminal conspiracy). By definition this means it wasn’t a witch hunt. So now Trump is praising the investigation and Mueller, who he had up until now been criticizing and explicitly saying is not legitimate. I doubt this will create any cognitive dissonance. They will just call it a “failed witch hunt” – even though that makes no sense at all.