What limits did the right to trial by jury place on the monarch?

In medieval England, the right to trial by jury, which was enshrined as Chapter 39 of the Magna Carta, prevented monarchs from arbitrarily ordering the punishment of free men, states the Encyclopedia of Criminology. After the Magna Carta was signed in 1215, monarchs who failed to adhere to the rights it enshrined, such as the right to trial by jury, were forced to abdicate their thrones.

The Magna Carta was signed by King John, not because he wished to protect his subjects from subsequent monarchs, but as a means to appease rebellious barons, according to the Constitutional Rights Foundation. It was part of a suite of changes he introduced to safeguard his throne.