There is an old story about how medieval people used to test whether or not someone was a witch, and it goes like this: Throw them in a pond. If they sink into the water and drown, that means they weren’t a witch. If they float, that means they are a witch, so you haul them out and burn them to death. Either way, just getting accused of witchcraft was a death sentence, but medieval people were too dumb to realize it.

This story is wrong. It was popularized by Victorian writers who spread many false stories depicting people of the European middle ages as ignorant, illogical, and stupid. At best, we might attribute this story to the intellectual laziness of Victorians who didn’t bother to distinguish between the use of ducking victims in water as punishment or torture and the use of immersion in water to test those accused of witchcraft or other crimes. At worst, we can see it as part of a concerted effort by Protestant English and American writers to paint contemporary Catholics as the benighted heirs to an age of barbarity and unreason. The truth about testing witches in water is more complicated, though in some ways even worse.

Here’s how the water test actually worked. In some places, a person accused of witchcraft, heresy, or a variety of other offenses was lowered into a small body of water like a pond or a still river, generally with a rope tied around their waist or something similar for lifting them out again. They were allowed to float for a moment and a jury selected from the surrounding community (or sometimes a priest) observed whether their body seemed to float on the surface or sink into the water. It was believed in some places and times that water would reject an unholy person, so their body would float high, while a blameless person would sink into the water. Once the jury had had a chance to observe the result, the accused was pulled out again and the jury gave its judgment.

No one was supposed to drown, neither the innocent nor the guilty. They were not left in the water for long, and whatever device was used to lower them in could quickly pull them up again. No doubt there were sometimes mishaps, as there can be whenever people are around the water, but being cleared of suspicion did not require drowning.

Trial by ordeal, which included not only the water test but other tests including carrying heavy stones or hot metal, reaching into a boiling cauldron, and similar challenges to physical endurance, was common in the legal traditions of some peoples in early medieval Europe. Such tests were an attempt to create objective tests for complicated questions about an accused person’s character, morals, and other hard-to-quantify qualities.

Trials by ordeal largely disappeared from European custom by the thirteenth century, but there was a revival during the witch-hunting hysteria of the early modern period when variations of the trial by water were used along with other methods of torture to extract false confessions from victims. In those cases the accusation alone was, for most people, a death sentence, since the point of the various “tests” was to compel a confession, not to arrive at a judgment.

The important element in a trial by ordeal is the community jury. Someone had to judge whether the accused was floating or not, which is not as obvious as it may sound. Human bodies are naturally buoyant, but not so much as to float on top of the water like a pool noodle. In the water, everyone kind of floats, and everyone kind of sinks. Distinguishing between how much floating is enough and how much is too much is no simple task. Those who were called for the jury were typically members of the accused’s village, extended family, or social network. They did not go into the test with an unbiased opinion but took with them all their knowledge, history, and feelings about the accused.

The floating ordeal gave the jury an objective external event to lodge those existing prejudices in. Those who went in with a poor opinion of the accused were likely to think that they floated too much, while those who went in well-disposed to the accused were likely to think they had adequately sunk into the water. Attaching those preexisting prejudices to an external event like the water test allowed the members of the jury to treat those prejudices as if they were objective facts and condemn or exonerate the accused with a clear conscience, as their own leanings dictated.

It is this fact about trials by ordeal that makes them, in some ways, even more horrible than the foolish heads-you-drown/tails-you-burn legend. If you were condemned by the water test it didn’t mean you just randomly floated too much. It meant that your own neighbors hated you so much they wanted to see you dead, they just didn’t feel comfortable saying so until the trial gave them permission to.

Post edited to correct a spelling error.

Image: Illustration of a trail by water via Wikimedia (late 12th c.; manuscript illustration)

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