Under what condition can a Marine be confined to bread and water as a result of NJP?

The confinement to bread and water as a result of Non-Judicial Punishment (NJP) for a Marine is specifically applicable while they are embarked aboard a Naval vessel. This practice is rooted in historical traditions of naval discipline and is viewed as a form of punishment relevant to the unique environment of a ship, where resources and other forms of punishment may be more limited.

Being aboard a Naval vessel often subjects Marines to the naval customs and practices that differ from the conditions on land. This rule emphasizes maintaining order and discipline at sea, where the close quarters and operational nature of naval missions necessitate strict adherence to military regulations. The confinement to bread and water is thus authorized under certain circumstances as a disciplinary method during this period.

While other options such as being on leave, stationed overseas, or during a training exercise may involve disciplinary measures, they do not carry the specific provision that applies to confinement under NJP aboard a Naval vessel, making the condition of being embarked the correct context for this punishment.