Being that all we have to go on is a news article, I have mixed feelings about this.

Mixed chains of command create confusion. We don't know what the standing orders and special orders were, we don't know the Iraqi's chain of command's orders were, there are too many unknowns.

It may be a situation where the Marines and Centcom feel obligated to try the Marine as a show of fairness to assuage the Iraqi military, and that little to nothing will come of the trial.