Why is everyone being so tough on Ree? It's not his fault. He was under psychic influence from Deanna. Did they expel Data from Starfleet when Dr. Soong remotely took him over in "Brothers" and had him take over the ship? Did Chekov get court-martialled for going berserk under the influence of interphase space in "The Tholian Web?" Not to mention the crazy and dangerous behavior of crewmembers whose behavior was externally altered in episodes like "The Naked Time," "Day of the Dove," "The Naked Now," "Fascination," "Bliss," you name it. Starfleet is not in the habit of punishing people for things they did when under external mental influence.
EDIT: The annotations for OaTS just went live.
Valid point, but I think under the circumstances the crew (especially Riker and Troi) were going a little too quickly to, "It's okay, it's not your fault." Said hearing shouldn't be written off as some paperwork formality, but a serious inquiry of how much it was external influence, and how much it was his own actions and instincts, and how culpable he is for that. A prosecutor would just have to A. ask Troi if she targeted psychic influence on Ree and B. point out that no one else in the room with Troi at the time freaked out and kidnapped her, and then the question would be turned back on Ree: how much of this was your own instincts, and how responsible are you, a sentient member of Starfleet, for the choices you made as a result of those instincts?
I'm not saying that there aren't significant citable examples of similar loss-of-conscious-control by Starfleet officers, but Ree's actions were severe, and the inquiry into them should be treated with more gravity than we were given.