A more thorough explanation:

Definition: Former punishment is a rule in military law that states that if a person has already received nonjudicial punishment for a minor offense, they cannot be tried again for the same offense in a court-martial.

Example: Let's say a soldier was caught using their phone during a briefing and was given a punishment of extra duty. Later, the same soldier is accused of the same offense and is brought to a court-martial. However, because they already received nonjudicial punishment for the same offense, the court-martial cannot try them again for the same offense.

This rule is in place to prevent double jeopardy, which is when a person is tried twice for the same offense. It also encourages commanders to use nonjudicial punishment for minor offenses instead of immediately resorting to a court-martial.