We have long argued that perjury and obstruction-of-justice charges against Lewis Libby should never have been brought. Now, we’ve had a chance to watch Libby’s trial, to hear the witnesses, to see the evidence. And after all that, our conclusion is: This is a case that should never have been brought.

CIA-leak prosecutor Patrick Fitzgerald alleges Libby lied when he told a grand jury that he originally learned about the identity of Valerie Plame Wilson from Vice President Dick Cheney, then forgot it amid the press of other work, and then was surprised to hear about it during a conversation with NBC’s Tim Russert. To prove his case, Fitzgerald called a series of witnesses to challenge Libby’s memory by testifying that they told him, or talked to him, about Mrs. Wilson.

But many of those witnesses had memory problems of their own. There was Judith Miller, the former New York Times reporter, who testified that Libby told her about Mrs. Wilson during a meeting on June 23, 2003. Miller had a very clear memory of the meeting, telling the jury that Libby “appeared to me to be agitated and frustrated and angry.” It might have been powerful testimony, except that defense lawyers pointed out that when Miller first testified before the grand jury, she completely forgot about that supposedly critical June 23 meeting. It was only after she discovered a shopping bag full of notebooks under her desk at the Times that she saw some old notes and remembered the meeting. She went back to the grand jury and changed her story.

Then there was Robert Grenier, the former top CIA official who testified that he told Libby about Mrs. Wilson on June 11, 2003. But when Grenier originally testified before the grand jury, he couldn’t remember what he had told Libby. It was only a year later, Grenier testified, when reading newspaper accounts of the case, that he had a “growing” recollection that he in fact told Libby about Valerie Plame Wilson. He went back to the grand jury and changed his story. “Does your memory improve with time?” defense lawyer William Jeffress asked mockingly.

And then there was the star prosecution witness, NBC’s Tim Russert. Russert stuck to his story — that he never told Libby about Mrs. Wilson — but the defense team challenged his account by pointing to a document written by an FBI agent after an early interview with Russert. “Russert does not recall stating to Libby, in this conversation, anything about the wife of former ambassador Joe Wilson,” the agent wrote, but Russert “could not completely rule out the possibility that he had such an exchange.” At trial, that doubt was gone — another memory that improved over time, the defense suggested.

By the end, it was clear that Fitzgerald’s case was based on he-said, she-said testimony from witnesses who suffered the same kind of faulty memories that Libby claims. And that’s before one considers that Libby wasn’t even the source of the celebrated CIA leak; the original leaker was, of course, former top State Department official Richard Armitage. That’s also before one considers that Fitzgerald was unable to charge anyone, Libby included, with any underlying crime in the case.

Is this any basis for five felony charges that could send Libby to jail for a maximum of 30 years? The answer is emphatically “No.” We’ve now seen Fitzgerald’s best evidence, and we’re more certain than ever: This is a case that should never have been brought.