WASHINGTON – Former FBI Director James Comey on Thursday essentially laid out an obstruction of justice case against President Donald Trump and suggested senior leaders in the bureau might have actually contemplated the matter before Trump removed him as director.

Comey did not explicitly draw any legal conclusions. Whether justice was obstructed, he said, was a question for recently appointed special counsel Robert Mueller. But he said Trump's request to terminate the FBI's investigation into former national security adviser Michael Flynn left him "stunned," and senior FBI officials considered it to be of "investigative interest."

Of particular concern, Comey said, was that Trump asked other officials to leave him alone with his FBI director in the Oval Office before saying of Flynn: "He is a good guy. I hope you can let this go."

"Why did he kick everybody out of the Oval Office?" Comey said. "That, to me as an investigator, is a very significant fact."

Legal analysts have said previously that there was reason to believe Trump might have obstructed justice – both in asking him to shut down the probe into Flynn and then, later, in firing Comey. Comey's testimony, they said Thursday, clarified and bolstered the case.

Comey testified that he was skeptical of Trump almost from the outset, and he decided to document their interactions because he was "concerned [Trump] might lie about the nature of our meeting."

His concerns were realized almost immediately. In a meeting just after Trump took office, Comey said, Trump brought up his job as FBI director and asked for loyalty. Comey said he felt Trump was "looking to get something in exchange for granting my request to stay in the job." The FBI director is generally appointed to a 10-year term to avoid political influence.

The next month, after a counterterrorism briefing, Comey testified that Trump asked him to stay for a one-on-one conversation. He said both Attorney General Jeff Sessions and Trump's son-in-law and close adviser Jared Kushner lingered behind – in Comey's view, because they were leery of what might happen next.

When they left, Comey said, Trump said he hoped Comey would shut down an investigation of Flynn. At the time, Comey said, Flynn was "in legal jeopardy," as agents were investigating him for his contacts with Russians and "whether there were false statements made to government investigators."

Comey said – as he did in written testimony – that the president had not asked him to shut down the broader probe of possible coordination between the Trump campaign and the Kremlin to influence the 2016 election. But he said the request on Flynn was nonetheless "very disturbing" and other officials in the bureau were "as shocked and troubled by it as I was."

Comey allowed, under questioning from Sen. James Risch (R., Idaho) that Comey did not outright give him an order.

"He did not direct you to let it go?" Risch asked.

"Not in his words, no," Comey said.

But Comey later said he took the president's assertion as akin to a command.

"I took it as a direction," Comey said. "This is the president of the United States, with me alone, saying 'I hope this.'"

Comey also noted that he was fired – by the president's own account – because of the Russia investigation.

Cornell Law Professor Jens David Ohlin said that he understood "why the Republicans would want to focus on 'hope' versus 'direct,' but I don't think it makes any difference."

"Trump made his wishes clear and fired Comey when his wishes weren't respected," Ohlin said. "It doesn't matter whether it was an order or not. What matters is the action that Trump took when it became clear that Comey was continuing the investigation."

While Mueller could ultimately conclude Trump obstructed justice, previous Justice Department legal opinions say he could not indict or charge a sitting president. Congress, though, could impeach the president – which makes Comey's testimony before legislators all the more important.

Barak Cohen, a former federal prosecutor now in private practice at Perkins Coie, said he believed Comey was "walking a fine line," both "trying to convey how he interpreted the president, but also admitting that there might have been other ways to interpret what the president said."

But Comey's assessment of the situation, he said, was critically important.

"He was there, he heard the president's tone and saw his body language – things that shape whatever the president was trying to express," Cohen said. "That's why direct evidence of someone who witnesses an alleged crime is so important."

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