Final answer:
The practice of throwing someone into a lake to judge innocence or guilt is known as Trial by Ordeal, specifically trial by water, which is an ancient form of judicial practice where divine intervention was expected to reveal the truth.
Step-by-step explanation:
When a person is thrown into a lake to determine their innocence or guilt, it is known as Trial by Ordeal. Specifically, this could be considered a form of trial by water. In this ancient practice, if the accused floated, they were considered guilty, as the water had 'rejected' them, but if they sank, they were seen as innocent. This method was based on the belief that divine forces would intervene to show the truth. Trial by fire was another form of ordeal where the accused had to hold or walk over hot coals, and their injuries were later inspected for healing as a sign of innocence or guilt. Trial by combat was a judicial duel where the disputing parties fought, and the winner was deemed right. These ordeals were commonly used in medieval times before the emergence of more modern legal processes like trial by jury or trial by inquisition, which relied on investigation and evidence rather than divine signs.