This is a partial transcript of "Special Report With Brit Hume" from Dec. 28, 2005, that has been edited for clarity.

JIM ANGLE, GUEST HOST: The controversy over the NSA program to eavesdrop on terrorists calling the United States generated another round of questions today as defense attorneys for suspected terrorists, or even those who have already pled guilty, say they will challenge the evidence against their clients. That is just one part of a coming battle in the courts and with Congress over the president’s authorization for electronic surveillance without warrants.

To help us unravel some of this, we are joined with Robert Turner of the Center for National Security Law at the University of Virginia and a former counsel to the intelligence oversight board back in the ‘80s. Bob, thanks for joining us.

ROBERT TURNER, CENTER FOR NATIONAL SECURITY LAW: I’m delighted to be here, Jim.

ANGLE: Let me ask you first about this issue that has risen today. Defense lawyers for some terror suspects, some who are still facing trial, some already in detention, some even pled guilty, what effect do you think the fact that we now know there was some surveillance program, we don’t know if these people were involved, but what effect is that likely to have on these criminal cases?

TURNER: Well, I’m not a criminal law expert, but my guess is it will not overturn their convictions. What it might do is force the revelation of material that will be very helpful to Al Qaeda and its allies. That, to me, is the big harm.

I think when people have pled guilty, the odds are very good that they are guilty, and this type of process where you use information gathered for intelligence purposes in a criminal process is fairly well established now.

ANGLE: Yeah, usually intelligence is gathered to prevent bad things from happening, not to pursue a criminal indictment. So it gets tricky when you are try to move from one area to the other.

TURNER: Well, for many years, we built a wall in the Justice Department to keep the intelligence people and the law enforcement people from communicating with each other.

Now part of this is a natural friction. The intelligence people survive by keeping things secret. They have to protect sources and methods. Law enforcement people survive by getting convictions based on making information public. So some friction is inevitable.

But since 9/11, we have realized that this was not necessary under the constitution or the laws and we have torn down the wall at least to a degree.

ANGLE: Now on the broader issue, critics say that the president has done something illegal here, that he has broken the law, perhaps even committed an impeachable offense. You argue that is not the case. Why not?

TURNER: Well, the question is what is the higher law? What you have is a statute passed in 1978 by Congress to which every president since then, including Jimmy Carter and Bill Clinton have said does not take away the constitutional powers vested in the president by the constitution.

There is a very long history going back even before the constitution was written of the founding fathers understanding that Congress could not keep secrets and John Jay himself explained that under the new constitution, this was during the ratification debates, the president would be let free to manage the business of intelligence as prudence might suggest. And throughout nearly 200 years of our history, it was understood that neither the courts nor Congress had any role in the intelligence business. That was an exclusive presidential prerogative.

ANGLE: Now, members of Congress will say, especially the critics will say, look, we passed the law you were talking about in 1978, the Foreign Intelligence Surveillance Act, and created a FISA court to deal with these things, precisely because we wanted to govern how the president exercised his power to use wiretaps.

TURNER: I think you are exactly right. And the same reason they passed the war powers resolution trying to control how the president made decisions in the military area short of war. And I think there is a broad recognition that now they exceeded their constitutional power there just as I believe — I worked in the Senate when FISA was passed. And it is my view then, and it’s my view now that they were usurping presidential power.

All of the presidents have said the president has power to conduct warrantless national security — foreign national security wiretaps for counterterrorism, counterintelligence purposes, and every president has said while we find the FISA statute to create a useful process, it does not take away from the president the higher power, the independent power given to him by the American people through the Constitution that he is using to try to save lives. That is the key here; this is the purpose for these intercepts — to try to identify terrorists and to stop attacks on the American people.

ANGLE: Now, you know, it’s interesting, because a lot of the critics say flatly, this is illegal, that it is clearly illegal that we know it’s illegal, although none of us really know exactly what the NSA is doing here. You take the opposite position and say it is clearly legal. How is it that we can have such different views of the same act?

TURNER: Well, first of all, at issue here, the president may well be violating terms of the statute. I think that’s arguable. The statute is somewhat vague in a few areas. But if he has independent authority, as every president has claimed, as every attorney general has claimed, as Congress has repeatedly acknowledged, even in the 1968 crimes bill that set up the wiretap procedure, Congress exempted the president’s national security wiretaps from coverage. They understood that was a constitutionally based power.

I think a lot of the commentary that I’ve heard from critics is just ignorant of this history of presidential control over intelligence, and also they are focusing only on the statute and not on the fact that the constitution gives the president powers.

We can only amend the constitution in certain ways. That does not include by a simple statute enacted by Congress. What the critics are claiming, or what they seem to be thinking, when Congress passes a resolution, it amends the constitution.

ANGLE: Got to go. Bob Turner, thanks very much for joining us.

Watch "Special Report With Brit Hume" weeknights at 6 p.m. EST.

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