This is a partial transcript from "The O'Reilly Factor," April 25, 2006, that has been edited for clarity.

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BILL O'REILLY, HOST: "Back of the Book" segment tonight. As you may know, a British court recently ruled that the author of "The Da Vinci Code," Dan Brown, did not steal material from other authors Michael Baigent and Richard Leigh, who had written a book called "Holy Blood, Holy Grail" which they said Brown took from.

Mr. Baigent currently has a new book out called "The Jesus Papers: Exposing the Greatest Cover Up in History". He joins us now.

We'll get to your book in a moment. Why do you think you lost the case?

MICHAEL BAIGENT, AUTHOR, "THE JESUS PAPERS": Well, it was quite clear that Brown had taken a lot of our material, but it didn't constitute enough of an infringement by British law. Legally, the judge found against us.

O'REILLY: But I mean, don't all fiction authors read other people and then cult together a mystery based upon it? I guess it was the Mary Magdalene stuff that you were...

BAIGENT: All of us writers, we produce intellectual property. We have to defend other writers' intellectual property and we have to defend our own.

O'REILLY: I understand.

BAIGENT: We have to acknowledge where we take our stuff from.

O'REILLY: The theory that Mary Magdalene and Jesus were married, that was what was in play in this court case, correct?

BAIGENT: That was one of the things in play. I mean, that wasn't our theory. This has been around for awhile. I mean, our particular, what we introduced into the story was the idea of the grail as the person, the idea of the grail being Mary Magdalene, the womb, the child. The identification of a person within this multi-faceted...

O'REILLY: That they had a child together, Jesus and Mary Magdalene? Is that what you're saying?

BAIGENT: Why not?

O'REILLY: Well, for one reason, sacrilege. And then a lot of people get angry when you mess around with a legend or...

BAIGENT: But is it more plausible that someone should be married and a child?

O'REILLY: More plausible. Because I've been reading your book. And I've got to say I don't buy what you're saying. I don't think you back it up. I don't think it's scholarship. I think it's your imagination what might have happened. And it's written down to sell books.

And let me just point to two things. I base all of my analysis on fact. And the two factual — and you know this better than anyone — archives we have on the crucifixion of Jesus are from the Roman historian, Tacitus, who basically said that Jesus was executed in the extreme penalty at the hands of Pontius Pilate, extreme penalty during...

BAIGENT: During the reign of the Emperor Tiberius.

O'REILLY: Right. And Josephus Flavius, in Jewish antiquities, basically says that Pilate, at the suggestion of the Sanhedron, condemned him to the cross. So now we have two historical...

BAIGENT: We can't accept Josephus' statements. No one accepts Josephus. The earliest manuscript in Josephus is the 13th century, the 12th century. No, no, no. We don't have anything we can hold in our hands. As a historian, I have to deal with what I can hold in my hand.

O'REILLY: You discount the Hebrew historian Josephus across the board?

BAIGENT: Not at all. I discount the comments he has to make on Christianity. I think those are later editions.

O'REILLY: All right.

BAIGENT: But for many reasons, I don't think we can justify them as being original.

O'REILLY: Here's my deal. You'll sell books by saying there was a cover-up on Jesus. You'll sell some. But why? You can't prove it. You know you can't prove it. You admit you can't prove it. Why bother?

BAIGENT: There is a cover-up. In the fourth century, they created this theological figure of Jesus. I'm a historian. I'm interested in the historical Jesus.

O'REILLY: The gospel was written long before that.

BAIGENT: Jesus never claimed to be God. Jesus never tried to start a religion. He promulgated a faith of forgiveness, of love, of compassion. You cannot go afar from that.

O'REILLY: You can't prove what you're saying. This is a theory that you have.

BAIGENT: How can we prove anything about the New Testament?

O'REILLY: The best available evidence comes from the gospels, which is written way before you say it, and from Tacitus. So...

BAIGENT: No, Tacitus is the only historian that we can rely on. We know he was crucified.

O'REILLY: But you say he didn't die on the cross.

BAIGENT: No. Well, this is the interesting thing.

O'REILLY: You're just making it up.

BAIGENT: No, no, not at all.

O'REILLY: Come on.

BAIGENT: What did Pilate have to do?

O'REILLY: I read it. I read what you said.

BAIGENT: He only had to get the taxes to Rome and keep peace in Judea.

O'REILLY: You don't have any shred of evidence in your book backing the theory up. You should write fiction like Brown.

BAIGENT: I would make more money.

O'REILLY: But it is fiction.

BAIGENT: No, it's not fiction. No, no, Bill, you've got it all wrong. What we're looking at, as a historian, you have to come to the conclusion that Pilate had this impossible dilemma. He couldn't execute Jesus. Because if he did, his job would be on the line.

O'REILLY: All right. I have to say, and I have to go. I am a historian. I taught history, I have a degree. I don't buy what you say at all. It's interesting. It's amusing. I think you should write fiction.

Mr. Baigent, thanks very much.

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