When in doubt, do not act; but a common error sometimes passes into law.

Explanation

A long-standing and universal mistake of law may, over time, acquire the force of law through common acceptance — but fresh doubts should be resolved by inaction, not innovation.

Where this applies

• A widespread legal error has been followed for so long that people rely on it.
• Everyone has been interpreting a law incorrectly for decades, and now someone challenges it.

See also

• 1.3.1 Custom is the best interpreter of the law.
• 12.4.1 In doubtful cases, the more favorable construction is to be preferred.