Spencer Tracy (not surprisingly) had two of the best scenes. One was his speech at the announcement of the verdicts. I’ve always thought that was such a masterfully written summary of the principles, but when you write it down and read it, it seems rather dry and spare. So that reaction owes a tremendous amount to his performance. Here is a transcript as best I could capture it (I hope this is part of fair use), with my favorite parts highlighted. Much better is to watch this performance. https://www.youtube.com/watch?v=N3BwK51YFgQ
Simple murders and atrocities do not constitute the gravamen of the charges in this indictment. Rather, the charge is that of conscious participation in the nationwide, government-organized system of cruelty and injustice in violation of every moral and legal principle known to all civilized nations. The tribunal has carefully studied the record, and found therein abundant evidence to support beyond a reasonable doubt the charges against these defendants. Herr Rolfe, in his very skillful defense, has asserted that there are others who must share the ultimate responsibility for what happened here in Germany. There is truth in this. The real complaining party at the bar here in this courtroom is civilization. But the tribunal does say that the men in the dock are responsible for their actions. Men who sat in black robes in judgment on other men; men who took part in the enactment of laws and decrees the premise of which was the extermination of human beings; men who in executive positions actively participated in the enforcement of these laws, illegal even under German law.
The principle of criminal law, in every civilized society, has this in common: any person who sways another to commit murder, any person who furnishes the legal weapon for the purpose of the crime, any person who is an accessory to the crime, is guilty. Herr Rolfe further asserts that the defendant Janning was an extraordinary jurist, and acted in what he thought was the best interest of his country. There is truth in this also. Janning, to be sure, is a tragic figure. We believe he loathed the evil he did. But compassion for the present torture of his soul must not beget forgetfulness of the torture and death of millions by the government of which he was part. Jannings’ record and his fate illuminate the most shattering truth that has emerged in this trial – if he, and the other defendants, had been degraded perverts, if all of the leaders of the Third Reich had been sadistic monsters and maniacs, then these events would have no more moral significance than an earthquake, or any other natural catastrophe. But this trial has shown that under a national crisis, ordinary and even able and extraordinary men can delude themselves into the commission of crimes so vast and heinous that they beggar the imagination. No-one who has sat through the trial can ever forget them: men sterilized because of political belief, a mockery made of friendship and faith, the murder of children. How easily it can happen.
There are those in our own country too who speak of the protection of country, of survival. A decision must be made, in the life of every nation, at the very moment when the grasp of the enemy is at its throat, when it seems that the only way to survive is to use the means of the enemy, to rest survival on what is expedient, to look the other way. Only, the answer to that is, survival as what? A country isn’t a rock, it’s not an extension of oneself. It’s what it stands for. It’s what it stands for when standing for something is the most difficult.
Before the people of the world, let it now be noted that here in our decision this is what we stand for: justice, truth, and the value of a single human being.
The other best scene was his meeting with Burt Lancaster’s character, the last scene (or almost?). Just crushing any remaining sympathy the viewer might have had with the German.