The robot said, "Partner Elijah, I am afraid that this theory is quite untenable. As you know, it is impossible for Commissioner Enderby to have murdered Dr. Sarton."
"Listen, then. Listen to me. Enderby begged me to take the case, not any of the men who over-ranked me. He did that for several reasons. In the first place, we were college friends and he thought he could count on its never occurring to me that an old buddy and respected superior could be a criminal. He counted on my well-known loyalty, you see. Secondly, he knew Jessie was a member of an underground organization and expected to be able to maneuver me out of the investigation or blackmail me into silence if I got too close to the truth. And he wasn't really worried about that. At the very beginning he did his best to arouse my distrust of you, Daneel, and make certain that the two of us worked at cross-purposes. He knew about my father's declassification. He could guess how I would react. You see, it is an advantage for the murderer to be in charge of the murder investigation."
The Commissioner found his voice. He said, weakly, "How could I know about Jessie?" He turned to the robot. "You! If you're transmitting this to Spacetown, tell them it's a lie! It's all a lie!"
Baley broke in, raising his voice for a moment and then lowering it into a queer sort of tense calm. "Certainly you would know about Jessie. You're a Medievalist, and part of the organization. Your old-fashioned spectacles! Your windows! It's obvious your temperament is turned that way. But there's better evidence than that.
"How did Jessie find out Daneel was a robot? It puzzled me at the time. Of course we know now that she found out through her Medievalist organization, but that just shoves the problem one step backward. How did they know? You, Commissioner, dismissed it with a theory that Daneel was recognized as a robot during the incident at the shoe counter. I didn't quite believe that. I couldn't. I took him for human when I first saw him, and there's nothing wrong with my eyes.
"Yesterday, I asked Dr. Gerrigel to come in from Washington. Later I decided I needed him for several reasons, but, at the time I first called him, my only purpose was to see if he would recognize Daneel for what he was with no prompting on my part.
"Commissioner, he didn't! I introduced him to Daneel, he shook hands with him, we all talked together, and it was only after the subject got around to humanoid robots that he suddenly caught on. Now, that was Dr. Gerrigel, Earth's greatest expert on robots. Do you mean to say a few Medievalist rioters could do better than he under conditions of confusion and tension, and be so certain about it that they would throw their entire organization into activity based on the feeling that Daneel was a robot?
"It's obvious now that the Medievalists must have known Daneel to be a robot to begin with. The incident at the shoe counter was deliberately designed to show Daneel and, through him, Spacetown, the extent of anti-robot feeling in the City. It was meant to confuse the issue, to turn suspicion away from individuals and toward the population as a whole.
"Now, if they knew the truth about Daneel to begin with, who told them? I didn't. I once thought it was Daneel himself, but that's out. The only other Earthman who knew about it was you, Commissioner."
Enderby said, with surprising energy, "There could be spies in the Department, too. The Medievalists could have us riddled with them. Your wife was one, and if you don't find it impossible that I should be one, why not others in the Department?"
The corners of Baley's lips pulled back a savage trifle. "Let's not bring up mysterious spies until we see where the straightforward solution leads us. I say you're the obvious informer and the real one.
"It's interesting now that I look back on it, Commissioner, to see how your spirits rose and fell accordingly as I seemed to be far from a solution or possibly close to it. You were nervous to begin with. When I wanted to visit Spacetown yesterday morning and wouldn't tell you the reason, you were practically in a state of collapse. Did you think I had you pinned, Commissioner? That it was a trap to get you into their hands? You hated them, you told me. You were virtually in tears. For a time, I thought that to be caused by the memory of humiliation in Spacetown when you yourself were a suspect, but then Daneel told me that your sensibilities had been carefully regarded. You had never known you were a suspect. Your panic was due to fear, not humiliation.
"Then when I came out with my completely wrong solution, while you listened over trimensional circuit, and you saw how far, how immensely far, from the truth I was, you were confident again. You even argued with me, defended the Spacers. After that, you were quite master of yourself for a while, quite confident. It surprised me at the time that you so easily forgave my false accusations against the Spacers when earlier you had so lectured me on their sensitivity. You enjoyed my mistake.
"Then I put in my call for Dr. Gerrigel and you wanted to know why and I wouldn't tell you. That plunged you into the abyss again because you feared - "
R. Daneel suddenly raised his hand. "Partner Elijah!"
Baley looked at his watch. 23:42! He said, "What is it?"
R. Daneel said, "He might have been disturbed at thinking you would find out his Medievalist connections, if we grant their existence. There is nothing, though, to connect him with the murder. He cannot have had anything to do with that."
Baley said, "You're quite wrong, Daneel. He didn't know what I wanted Dr. Gerrigel for, but it was quite safe to assume that it was in connection with information about robots. This frightened the Commissioner, because a robot had an intimate connection with his greater crime. Isn't that so, Commissioner?"