ABC News broadcast less than an hour of former FBI Director James Comey's interview with George Stephanopoulos on Sunday night, focusing mostly on his relationship with President Trump, but the network also published a transcript of the entire five hours of conversation. And a lot of that talk centered around Comey's very public, hotly debated role in the email investigation of Hillary Clinton. Here are some things we learned:

1. Comey knew by spring 2016 the Justice Department wasn't going to prosecute Clinton.

Comey disclosed publicly that the FBI was looking into whether Clinton's emails violated federal law in September 2015, but by May 2016, he was pretty sure there was no prosecutable case. "We had looked all around and scrubbed thousands and thousands and thousands of Hillary Clinton's emails," Comey said. "We had a very clear picture after nine or 10 months of investigation of this case." In fact, he added, "anybody who's actually done investigations knows that if you've been investigating something for almost a year and you don't have a general sense of where it's likely to end up, you should be fired because you're incompetent." After investigators interviewed Clinton on July 2, they determined there was no case.

2. But the emails found on Weiner's laptop were different in important ways.

But Comey, controversially, informed Congress two weeks before the election that the FBI was reopening the investigation, and Congress promptly told everyone else, arguably paving the way for Trump's upset victory. The Clinton emails that FBI investigators found on Anthony Weiner's laptop were from Clinton's BlackBerry domain, and that could have changed the calculus for prosecutors, Comey told Stephanopoulos. "She used a BlackBerry for the first three months or so of her tenure as secretary of state before setting up the personal server in the basement. And the reason that matters so much is, if there was gonna be a smoking gun, where Hillary Clinton was told, 'Don't do this,' or, 'This is improper,' it's highly likely to be at the beginning."

3. Comey was scared of leaks from rogue FBI agents.

Comey said one reason he felt it necessary to disclose the new batch of Clinton emails in late October was because he was concerned the information would leak out anyway. Stephanopoulos asked if he was "dealing with a rogue element of FBI agents and former FBI agents up in New York," and Comey said he knew there "appeared to be leaks about criminal investigation of the Clintons coming out of New York," and he "commissioned an investigation to find out" where the leaks were coming from. "I don't know what the investigation found," he added. The New York investigators have "a different culture" than the counterintelligence team in Washington, and "there'd been enough up there that I thought there was a pretty reasonable likelihood that it would leak."

4. He didn't reveal the Trump-Russia investigation because it would tip off Trump people.

Comey confirmed that the investigation into possible Trump campaign collaboration with Russia was sparked by adviser George Papadopoulos talking to an Australian diplomat, which the FBI learned about in late July, and "the FBI didn't get any information that's part of the so-called Steele dossier, as I understand it, until after that." Comey said he decided to confirm the Clinton email case because it "began with a public referral" and "we were actually investigating the candidate herself," but he declined to publicly discuss the Trump counterintelligence investigation before the election because Trump wasn't a target; "we didn't know what we had, and we didn't want to tip them off that we were looking at them."