Final answer:
A sergeant (E-5) or above in the military may be tried without a grand jury indictment according to Amendment V of the U.S. Constitution, especially during wartime or public danger, under the Uniform Code of Military Justice.
Step-by-step explanation:
When considering the circumstances where a sergeant (E-5) or above in the military service may be held to answer for charges, it's important to reference the Amendment V of the U.S. Constitution. This amendment specifies that no person shall be held to answer for a capital or otherwise infamous crime without an indictment of a Grand Jury, except in cases involving the military forces during wartime or public danger.
In the military context, particularly under the conditions of war or public danger, service members such as sergeants can be subjected to a different judicial process, which includes courts-martial and military tribunals, bypassing the typical civilian grand jury process. This is because the military operates under the Uniform Code of Military Justice (UCMJ), which allows for military commanders to convene courts-martial without the need for a grand jury indictment.