A more thorough explanation:

A bright-line rule is a clear and objective legal rule that provides a straightforward answer to a legal question. It is based on objective factors and allows parties to conduct their affairs in a way that avoids lawsuits. However, it may lack flexibility and may not consider individual nuances, which can lead to unfair outcomes.

An example of a bright-line rule is the legal age for drinking alcohol. In the United States, the legal drinking age is 21. This rule is clear and objective, and it applies to everyone equally. Anyone who is under 21 and caught drinking alcohol can be charged with a crime, regardless of their individual circumstances.

Another example is the rule that the party whose car is damaged in the front is responsible for a car accident. This rule is easy to understand and provides a clear answer to who is at fault in a car accident. However, it may not consider individual circumstances, such as if one party backed into the other.

These examples illustrate how bright-line rules can provide a clear and objective answer to legal questions. However, they may not always consider individual circumstances, which can lead to unfair outcomes.