What term describes the legal principle where opinions become precedents for future cases involving similar facts?

The correct term that describes the legal principle where opinions become precedents for future cases involving similar facts is "stare decisis." This principle is fundamental to common law systems, as it ensures consistency and predictability in the law by requiring courts to follow the rulings of previous cases, unless there is a compelling reason to overturn or differentiate from them.

Stare decisis promotes legal stability and fairness, allowing individuals and entities to rely on established legal interpretations when navigating the legal system. This concept emphasizes that similar cases should be decided in a similar manner, which helps to create a coherent body of law and informs judges, lawyers, and the public about legal expectations based on prior decisions.

In contrast, the other terms do not directly relate to the idea of legal precedents. Sources of law refer broadly to the origins of legal principles, legal sanctions are penalties imposed for violating laws, and judicial authority pertains to the power vested in courts to make legal judgments. None of these alternatives captures the essence of how past judicial opinions serve as guiding precedent for future cases, making "stare decisis" the appropriate choice.