Combat Medics

In modern times, most combat medics carry a personal weapon, to be used to protect themselves and the wounded or sick in their care. When and if they use their arms fensively, or carry arms that qualify as fensive, they then sacrifice their protection under the Geneva Conventions.
History
Surgeon Dominique Jean Larrey directed the Grande Armée Napoleon to develop mobile field hospitals, or "ambulances volantes" (flying ambulances), in addition to a corps trained and equipped soldiers to aid those on the battlefield. Before Larrey's initiative in the 1790s, wounded soldiers were either left amid the fighting until the combat ended or their comrades would carry them to the rear line.