Exactly what constitutes a crime in the U.S. Military? In the civilian-world, you can yell at your boss, and the worst that can happen is you get fired. In the Military, yelling at your boss can not only get you fired (with a bad-conduct discharge), but can send you to Military prison for up to a year (Article 89 and 91). Did you know that in the U.S. Military, it's against the law to jump off a Military ship into the water? (Article 134-30).
The Uniform Code of Military Justice (UCMJ) is the bedrock of military law. The UCMJ is a federal law, enacted by Congress. Articles 77 through 134 of the UCMJ are known as the "punitive articles," -- that is, specific offenses which, if violated, can result in punishment by court-martial.
I didn’t know it was against the law to jump off a ship! When I was on float in 2002, a guy stripped his clothes and jumped off ship. Whoever responded to it asked the guy if he knew what he was swimming in- the ship had dumped it’s sewage in the water. He came back on board. I never found out what punishment he got.