Trial is by water; no one can win. Drown and you're innocent, guilty, you swim...

Explanation: In the medieval period, witch hysteria was actually less intense than it would become, with the Catholic Church even occasionally denouncing belief in witches itself as superstition.

But in the early modern period, a wave of paranoia swept Europe regarding witches, hiding in plain sight! This would reach its fever pitch in the 1600s. An old medieval practice - usually applied to non witch related offenses - was used to determine guilt or innocence - trial by ordeal. Especially, trial by water.

If you sink after being tied and tossed into a deep body of water, you’re innocent. If you float or swim, you’re guilty.

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Adding to this, while the trial was supposed to be performed with a means of retrieving the individual if they sank, this was not always adhered to. For that matter, what counted as sinking could vary considerably depending on who was running the trial. If you had an enemy in town, they might wait for the bubbles coming to the surface to stop before declaring you innocent.