In court they would look for a devils mark on the person that is being accused.  If they did find a mark then that would mean that the person is guilty of being a witch.  Also they would prick the person that is being accused with a needle or pin.  If the person felt pain then they aren't a witch if they didn't then they are a witch. They did that because they thought that witches can't feel pain so if the person that was being accused did not scream  then they are automatically guilty of being a witch.

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