Evidence held by the CIA "is exculpatory evidence" and Al-Nashiri "will be entitled to it."
Here we have a significant Al Qaeda figure, an openly hostile alien, an individual that respects no laws, has signed no treaties, and who should be entitled to no rights whatsoever. He shouldn't even be alive. Yet his legal team acts like he's some sort of victim. The very fact that he has lawyers working on his behalf at all is ridiculous on its face. Apparently the CIA held Al-Nashiri at secret locations where he was waterboarded and subjected to various other interrogation techniques, some of which, like the waterboarding, amounted to torture.
So basically the CIA did what it was supposed to do. It held a notorious terrorist captive and attempted to extract information from him by various methods. Because terrorist rights supporters don't like those methods, that makes the CIA the bad guy, and an Al Qaeda terrorist a victim who is entitled to a legal defense -- never mind that he's an alien, a terrorist, and a enemy of the U.S. We are now allowing terrorists to use our legal system against us, to attack the very intelligence agency that is on the front line of defense against terrorism.
The CIA did make some serious mistakes. First, they allowed information to leak out about the black sites. The whole point of having secret detainment and interrogation facilities is that they allow you to operate in secret. If their existence becomes public knowledge, the usefulness of such sites is severely compromised. Their other major mistake was in leaving people like Al-Nashiri alive. No doubt CIA leaders never imagined that their country would be so unbelievably stupid as to allow terrorist enemies access to lawyers and the court system, or that a whole terrorist rights movement would take up the cause of our enemies; but they should have erred on the side of caution. In the future the CIA needs to take better care to preserve the secrecy of its operations. If terrorists need to be tortured for information, they should be eliminated when they are no longer useful. Given the current legal climate, the benefits of keeping them alive are not worth the possible costs.