Final answer:
The idea of 'precedent' or 'stare decisis' refers to judges making decisions based on prior rulings to maintain consistency in the legal system, with the flexibility to adapt to societal changes.
Step-by-step explanation:
The concept of 'precedent', sometimes referred to as stare decisis, is a foundational principle in law wherein judges make decisions based on previously decided cases. This principle emphasizes consistency and stability in the legal system by ensuring that similar cases are decided in a similar manner unless there's a justifiable reason to diverge. Judicial interpretations of precedent can evolve over time, allowing the law to adapt to new circumstances and societal changes. For instance, the landmark decision in Brown v. Board of Education overturned the 'separate but equal' doctrine of Plessy v. Ferguson due to changing legal perspectives on civil rights. Judges may interpret precedents and apply them to the case at hand, thereby also playing a role in policymaking.