In the end of A Few Good Men, the two Marines are acquitted on most charges but found guilty of conduct unbecoming a U.S. Marine and ordered to be dishonorably discharged from the Corps. Does it strike anybody else as completely unbelievable that after seeing the dramatic scene of Col. Jessup admitting to ordering the Marines to perform a "Code Red", the jury would go ahead and convict them of anything? Were they expected to refuse the order of a superior officer? The only explanation is an unsatisfactory one given by one of the accused Marines: "we were supposed to fight for Willie [the victim]". Is there a legal reason why this conviction might be legitimate? Or is it just to set up the closing line of the movie: "you don't have to wear a patch on your arm to have honor"?
No, this doesn't surprise me at all. What is conduct unbecoming? The court saying they did not behave as a Marine should behave. They should have known what was being asked of them was not in accordance with the Uniform Code of Military Justice (or UCMJ). They should have known the order was unlawful, and therefor not obeyed it. They should have taken it higher in the chain of command. The reason they were not get found guilty on the more serious charges was because COL Jessup admitted his involvement. Marines have a lot of pride. They expect their members to behave in a certain way. Obviously that wasn't happening in this case and they were discharged because of it.
EDIT: While "Conduct Unbecoming ..." does apply to officers only, Article 93 of the UCMJ would allow for discharge of these two individuals. In this article, it states:
Or they could also be charged under Article 81 which is:
If all else fails, there is a separation code which states:
So while they may have had the verbiage wrong in the movie (see Andrew's "woops"), they certainly could have been discharged for their actions. I would bet they used the term, "Conduct Unbecoming ..." because it sounds better than "For the Good of the Service" ... but that's JMHO.
To be perfectly frank, you're asking an extremely difficult and arguably unanswerable question.
There's an old legal saying I remember from my Law degree. "Justice depends on what the judge has had for breakfast". Different days can bring different results and in a trial like this, the military officers are free to come to whatever conclusion they want within legal reason (similar to a jury).
It's certainly plausible that the officers could have seen a Code Red as something that must be followed at all times, thus excusing the officers of any sanctions. Alternatively, they might have seen the Code Red as something to follow at all times provided there is no danger to US life, or provided it doesn't exist within a certain culture. My point is that, like a jury, the military officers are free to come to whatever decision they want on the matter.
However, on a final note - it was a movie and thus I do think it's probable the scene went the way it did to provide that iconic ending.
In real life, a person with zero defense experience would never get the position Kaffee did. Not to mention this rather important snippet of information from a former JAG officer:
So I would argue that if the crime did exist, it really depends on the jury's interpretation of events. But the crime doesn't exist, so you really just have to come to your own conclusions on it!