This is a partial transcript of The Big Story With John Gibson, September 30, 2003, that has been edited for clarity.

JOHN GIBSON, HOST: Investigating everyone in the White House to find out if the leak [into the identity of a CIA employee originated there] will be a huge undertaking. So, what will it involve?

FOX News senior judicial analyst Judge Andrew Napolitano can tell us about the search for evidence.

First of all, I still haven't got it clear why everybody thinks it was the White House. I mean, I read the quote, by syndicated columnist Robert Novak (search)… [who says an administration source told him Ambassador Joseph C. Wilson (search)'s wife was a CIA employee.] Now everybody is jumping to a conclusion because Karl Rove (search) is the president's muscle man.

JUDGE ANDREW NAPOLITANO, FNC SENIOR JUDICIAL ANALYST: Right.

GIBSON: And he extracts punishment from people if it needs to be done. But the fact is, if this information is known about the CIA wife, it's probably known widely among many departments in Washington, right?

NAPOLITANO: Yes. It would depend on how widely it was known. If it was known so widely that government officials took it for granted that her name was out there, then that would be a ratification, if you will, by the government of the United States, either under the Clinton administration when he was an ambassador or under the Bush administration.

And that, the government ratifying her name as a covert operative, is a defense to someone revealing it. In other words, the government will not successfully prosecute you for revealing something that the government itself ...

GIBSON: ... has already revealed.

NAPOLITANO: ... has already revealed.

GIBSON: We're talking in the area of hypothetical. But could the husband, Mr. Ambassador, Mr. Wilson himself, have been the method by which her identity was revealed?

NAPOLITANO: Well, of course. In his official capacity, when he was an ambassador, there are a lot of governmental duties and quasi-governmental duties, social functions to which Mrs. Wilson, who doesn't go by the name of Mrs. Wilson, would have been invited.

If he made it obvious or apparent or likely, “This is my wife and she works for the CIA, and she does covert things for the CIA,” that would be a revelation by the United States government of her status, which would then be a defense to anybody who is charged with revealing it subsequently.

GIBSON: The evidence against Rove is he pulled one of these tricks before, he has been in cahoots with John Ashcroft before. This he has got his fingerprints all over it because he's done this before. Now if I'm a prosecutor and I bring that to your courtroom ...

NAPOLITANO: That's not enough.

GIBSON: I don't even get in the door.

NAPOLITANO: No. No. And you wouldn't even get to first base if you asked Bob Novak who told you because he has a privilege, I say probably has a privilege, it depends on which state he was in, it goes by states.

The federal judges follow the privileges of the state courts in which they sit. If a state court, like New Jersey, has a privilege called the Shield Law, which protects a reporter from having to reveal his sources, the FBI can ask him who his source was until they're blue in the face. He doesn't have to answer and can't be punished for not answering. So their investigation will have to start elsewhere.

GIBSON: Judge Andrew Napolitano, I'm guessing we will continue to follow this.

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