Friday, October 12, 2012


Cross-Examining Galileo

The dynamics of examining witnesses have changed greatly during the evolution of the modern criminal justice system, but some things never change. The neglect of witnesses to read their previous statements before giving testimony is a common contributing factor in the success of cross-examination, and this has been true for centuries.

In April of 1633, when Galileo was summoned before the Inquisition, he faced some difficulties not confronted by the modern defendant. He had no lawyer, he had no right to remain silent, and he stood in danger of being tortured if the Inquisitors didn’t like what he said. Despite the differences, Galileo’s performance before the Inquisition has lessons for modern witnesses.

Years earlier Galileo had gotten into trouble with the Inquisition for teaching that the earth revolved around the sun. In that prior proceeding, he had been ordered not to teach Copernicus’ theory that the earth revolved around the sun as a fact. He was told that he could, however, teach it “suppositionally” as an interesting theory. He did some lobbying of the Pope and got permission to print a book on Copernican theory with the proviso that he had to make it clear that the sun really revolved around the earth. The book was supposed to be printed in Rome, and it was supposed to be vetted by the authorities in Rome. He printed it in Florence, and the authorities in Rome never saw the book until after it was printed.

His “Dialogue on the Two Great World Systems” is a classic of ground-breaking science, but it was also a prime example of the old proverb “Given an inch, some people want to take a mile.” Despite his pleas of ill health, he was ordered to appear before the Inquisition in Rome. Remarkably, we have a transcript of his testimony before the Inquisition.

In an exchange which began like a cross between a police interrogation and a prosecutorial cross-examination, Galileo did what many criminal defendants do today. He dug a hole for himself with his tongue. What follows is an extreme abridgment of Galileo’s testimony highlighting his missteps. We have recast the questions to conform with modern procedure, but the answers come straight from the transcript.

Q: If you were shown a copy of the “Dialogue” would you be able to recognize it?
A: I hope so. I hope that if the book is shown to me I shall recognize it. [The book was produced and Galileo examined it]. I know this book very well; it is one of those printed in Florence; and I acknowledge it as mine and that I wrote it.

Q: Did you write every word of that book?
A: I acknowledge all it contains as having been written by me.

Q: Were you summoned before the Inquisition in 1616?
A: In 1616 I came to Rome of my own accord.

Q: What was decided at that time?
A: It was decided by the Holy Congregation of the Index that this opinion, taken absolutely, is repugnant to Holy Scripture and is to be admitted only suppositionally, in the way that Copernicus takes it.

Q: Were you informed of the decision?
A: I was indeed notified of the said decision, and by whom.

Q: Did you receive permission to write the book?
A: After the above-mentioned injunction I did not seek permission to write the above-mentioned book which I have identified because I did not think that by writing this book I was contradicting at all the injunction given me not to hold, defend, or teach the said opinion, but rather that I was refuting it.

It is hard to characterize this statement as anything but a lie. There is no possible way to read Galileo’s book as touting the proposition that the sun goes around the earth, but the Father of Modern Science tried mightily to convince the Inquisitors that the book said something it didn’t. Unfortunately for Galileo, the Inquisitors had done something that Galileo apparently hadn’t done lately, they had read the book. As the questioning continued, Galileo continued to display a rather flexible attitude towards the facts, especially as it related to his evasion of explicit instructions about how, when, and where to publish the book. The questioning ended with Galileo saying that “with the said book I had neither held nor defended the opinion of the earth’s motion and sun’s stability; on the contrary, in the said book I show the contrary of Copernicus’s opinion and show that Copernicus’s reasons are invalid and inconclusive.”

If this had been a modern courtroom, the Inquisitor would have then embarrassed Galileo by calling his attention to the specific passages in the book where Galileo quite definitely said the earth went around the sun, and Galileo’s credibility would have been shattered before the jury. But there was no jury, there was just a panel of very intelligent, highly literate Inquisitors who had done something that Galileo hadn’t done lately—they had read the book.

At the conclusion of the hearing two things happened. The Inquisitors reported that Galileo was lying, and that he indeed taught that the earth revolved around the sun, and Galileo went and re-read his book. Galileo asked to go back before the Inquisitors and explain that he wasn’t lying, that it was all a big mistake. He was allowed to do so. He told the Inquisitors that when he first appeared before them, it had been three years since he’d read his book. He said he went back and re-read the book as soon as he could after the hearing and found to his horror that “it appeared to me in several places to be written in such a way that a reader, not aware of my intention, would have reason to form the opinion that the arguments for the false side, which I intended to confute, were so stated as to be convincing because of their strength. . . . If I had to write out the same arguments now, there is no doubt that I would weaken them in such a way that they could not appear to exhibit a force which they really essentially lack.” It was all a big mistake, he didn’t mean to do it, and could the Inquisitors please make some allowances for what Galileo called his “vain ambition, pure ignorance, and inadvertence.”

This defense, which is sometimes called the “pure heart, empty head” defense, might have worked if Galileo had made it on his first appearance before the Inquisition. He should have read his book before getting on the witness stand. Galileo made two more appearances before the Inquisitors trying to sell his “pure heart, empty head” defense, but the Inquisitors would have none of it. The record of his forth appearance states that “He was told to tell the truth, otherwise one would have recourse to torture.” Galileo never abandoned his “pure heart, empty head” defense, but he was in full retreat on his theory that the earth revolved around the sun. Apparently the Inquisitors were satisfied with his recantation of the Copernican theory. They didn’t torture him, but he did spend the rest of his life on house arrest.

The lesson is clear. Before putting any witness on the stand insist that the witness re-read any previous statements he has made.