Former National Security Agency chief Keith Alexander said Wednesday that the ex parte, non-adversarial nature of the Foreign Intelligence Surveillance Act court made for a “great debate” and that he was in favor of allowing third-party, friend-of-the-court observations on proceedings — amicus curiae — though he “forgot what you call it.”

But Alexander stopped short of advocating that both sides of a case be represented, as in a conventional U.S. court. “What I’m not for is telling a terrorist group that we’re gonna come after them,” Alexander added.

The USA Freedom Act, passed in June, changed some of the ground rules for U.S. surveillance and included provisions requiring discussion with an advisory amicus panel, to be comprised of privacy experts, for FISA court cases that involve novel or significant legal issues.

Alexander made the remarks about the FISA court in a debate Wednesday with The Intercept’s co-founding editor Glenn Greenwald.

The two men were discussing the impact of NSA surveillance programs on civil liberties at an information security conference hosted just outside of Washington by the computer company Hewlett-Packard.

“It wasn’t the NSA doing the wrong thing because NSA got a court order thirty-some times when I was there to go do this,” Alexander said, referring to the bulk collection of telephony metadata.

“From a secret court,” Greenwald replied.

“From a secret court that was set up,” Alexander responded before the two engaged in a back-and-forth on how the institution operates. Greenwald noted and Alexander confirmed that “only the government” is present during its proceedings.

“A secret court that only one side appears at, that’s the court that gave you –” Greenwald said, before Alexander jumped in, remarking: “It’s called the FISA Court.”

At the beginning of the discussion, the NSA chief from 2005 until 2014 said he didn’t regret impressing upon the agency an unapologetic desire to be omniscient. Specifically, when asked by the moderator, Alexander said he didn’t regret claiming, in the moderator’s words, that “in order to find a needle in the haystack, you have to collect the haystack.”

“The issue really comes down to two sets of events: 9/11 and our troops [being] in Iraq,” Alexander said. He then explained that during the height of the insurgency, the NSA decided to attempt to address “the future threat.”

“With that came the idea that if you could get the metadata about bad guys and who they’re talking to, you could interrupt their networks,” he said. “To get that information, you have to collect that all to know who are the bad guys and who to go after.”

Greenwald countered that the mindset has “really serious implications” on the concept of civilian rule in the U.S., whether or not it was effective as intended.

“The question was: ‘how do you surveil a foreign population in a country, in the middle of a warzone?’” Greenwald said. “This collect-it-all mentality became the answer.”