Maybe he did commit a crime (I don't think so), BUT it is NOT the state of comifornia's job to press charges. If there is enough evidence to bring charges against him then the Iraqi government should do it, or the International War Crimes Tribunial.
Personaly I'd like to meet the prosecuter face to face so I could punch his teeth in. This kids been through enough already without having to deal with this crap. No one really knows what happened and yeah I know the law is the law but unless you've been in combat, well things are just different. Things happen in the blink of an eye and you don't stop to ask yourself, "Gee I wonder if this is legal or not?" You just do whayever you think you have to do right then to survive.
If those Marines had 4 wounded insurgents in that building and they got orders to move out right now, yeah I would have popped them. You NEVER leave a living enemy behind you.