Once the investigation is complete and if the charges are found to be baseless.
Why are you so quick to take their freedom away on uncredible charges brought by people who routinely cut the heads, tongues, and noses off of their prisoners?
In the first place I didn't take their freedom away, the Marine Corps did. I'm familiar with the process because I spent quite a few years in the military. Because you, in your wisdom, proclaim the charges to be uncredible doesn't mean that the Marines shouldn't investigate. In case you haven't noticed recently other charges against other marines have been investigated and were ruled unfounded. Why are you opposed to the Marines taking the same route here and investigating the situation?
If the military didn't investigate accusations of crimes, crimes would proliferate, as would more accusations. If there is a perception that a crime took place, it will be investigated, both as a message to the outside world, and to the military itself. That's good PR, and it's good for maintaining discipline.
It sucks if you're wrongfully accused of a crime, and have to sit in lockdown until the investigation is over, and you're released. Still, the military is looking at the big picture. So, have patience. If they're innocent, they'll be free soon enough. In this war, the enemy isn't the pathetic band of miscreants who set roadside IEDs; it's the global media that amplifies their power a thousand fold. If we hand them propaganda victories like allowing accusations of atrocities to go uninvestigated, then we're slitting our own throats.
Handling our own like this is unfair, but we jeopardize our chances of victory by doing anything less.