"The U.S. government is trying to call this a fair trial, while stacking the deck so much against the defense and the accused that it can hardly be called a fair trial in any system in the world," he says.

He says the "Constitution has been stepped on."

"Leave aside our constitutional principles — which we should try to uphold irrespective of who the defendant may be — the Constitution has been completely stepped on throughout this entire process," he says.

As to the show trial, he says:

"We have a system where if someone's acquitted, they will not be set free," he says. "That is actually the very definition of a show trial."

As to why he resigned from the army: He says he had no choice, because the alternative would have been unethical.

Earlier this year, the Army instructed Wright to leave the team in order to complete a required graduate course with his promotion from Captain to Major. The course can be deferred for a variety of reasons; Wright had already deferred once. But his latest request for a deferral was denied without explanation.

"So really I only had two choices," he says. "I could either accept and voluntarily leave my own self from the case and my obligations to my client. Or I could refuse the orders."

He decided would be an ethical violation to abandon his client voluntarily, so he refused the orders. "And when you refuse the orders, you have to resign from the Army," he says.

As to the effect on his client:

"Here you have government attorneys who tell a defendant, 'I'm your attorney, I'm here to help you, and I'm going to be here 'til the end.' And half-way through this process, the U.S. government — the same government that tortures you, the same government that's trying to kill you, the same government that provides the public defender — now gets to control when defense attorneys come and go," he says.

The Army's response to his allegations:

"The Judge Advocate General denied the second deferral request because a suitable and competent military defense attorney replacement was available, Major Wright was not the lead or sole counsel, and it ensured Major Wright remained professionally competent and competitive for promotion."

...There is absolutely no Due Process violation for Mr. Mohammad by reassigning Major Wright to a new military duty station.

The response also says there were other ways Wright could have stayed on:

During the assignment process, MAJ Wright was offered the option of remaining on active duty as a mobilized reservist and not attending the graduate course, so that he could continue his representation of Mr. Mohammed if he felt, for example, his personal ethics demanded such.

I have no idea what the difference is between a "mobilized reservist" and a Major, but it sounds like they offered him a demotion of some sort.

Slate has more, including a comment from David Nevin, Mohammed's lead civilian lawyer who requested Wright join the team:

Nevin is the lead attorney on the case, but he views Wright as a peer and central member of the defense team, not just a junior lawyer he’s been assigned by the Army: “He is an excellent lawyer. A great team manager, organizer, thinker, just an incredible asset.”

Wright spent 50 to 60 hours a week on the case for the past three years:

He has represented Mohammed at every court proceeding since his arraignment in May 2012. Wright estimates he’s spent over 200 days in Guantánamo meetings with his client and attending court proceedings, and another 100 days in Europe and the Middle East attending capital defense training, developing a rapport with potential defense witnesses, and investigating facts crucial to the defense.

Another army lawyer who previously represented Gitmo detainees says:

“This was an opportunity to enhance the perception of legitimacy by saying publicly, ‘We’re going to grant this deferment, and in fact we will allow him to stay on as long as necessary because we recognize that the defense function is just as important as the prosecution function.’ They could have turned it into a PR bonanza instead of a PR disaster.”

As Slate aptly points out:

the KSM prosecution has been marred by intrusions into the proceedings by government entities, including the release of a half-million defense attorney emails to prosecutors, the discovery of hidden microphones placed by the FBI in attorney-client conference rooms, and allegations that FBI agents have been spying on defense teams. The Army’s reassignment of Major Wright away from U.S. v. Mohammed—which the defense team has portrayed as yet another symptom of lawlessness in Guantánamo—has only further diminished the appearance of legitimacy...