Bright-Line Rule

A bright-line rule (or bright-line test) is a clearly defined rule or standard, generally used in law, composed of objective factors, which leaves little or no room for varying interpretation. The purpose of a bright-line rule is to produce predictable and consistent results in its application. This is in contrast to its opposite, the fine line.

Bright-line rules are usually standards established by courts in legal Precedent or by legislatures in statutory provisions. Bright-line rules are often contrasted with balancing tests, where a result is dependent on weighing several factors, which could lead to inconsistent application of law or reduce objectivity.