I haven’t counted, but by now I have probably had more than 100 hours of conversation with Edward Snowden—either in person or at a keyboard and screen. Nearly all of them, until now, were as private as we could make them.

Last week we tried something different: a live-streamed video conversation at Princeton with an in-person audience of several hundred people. To keep things interesting, I pressed him to defend his position against serious critics and alternative points of view.

I won’t reprise the whole thing, with the full video of the talk available below, but a few things from our conversation stood out.

One thing that struck me was that Snowden and the issues he broached still draw crowds. The event took place on a sunny Saturday morning in an auditorium that seated 250. Turnout was high enough that Princeton’s Center for Information Technology Policy and the Program in Law and Public Affairs had to add a spillover room—and then another.

We talked a good deal about the first of Snowden’s published revelations: that the NSA and FBI keep records of who calls whom, and when, for nearly every U.S. telephone. The law that was secretly invoked to allow that program, Section 215 of the Patriot Act, is expiring on June 1. Five days after our conversation, the U.S. Court of Appeals for the Second Circuit ruled that the program was not lawfully authorized under that statute.

Snowden began the morning by arguing that all those phone records have not proved especially useful in countering terrorism. That is not the most interesting question to me, and it’s not likely that we can answer it with public evidence. But suppose it worked really well, I asked Snowden. The intelligence community says it cannot use narrowly targeted surveillance tools alone because only bulk collection is capable of finding unknown conspirators and foreign agents. Is that wrong?

Here Snowden took a philosophical turn to the “boundaries of our rights in society.” When it comes to information, any information:

Culturally the government has adopted a worldview that if it is out there, we should know it and have access to it. But this is radically different from the historical relationship of the people to the government.

Collecting the records of every phone call, he said, is like searching every home in case it holds a stash of illegal drugs:

Now they’re not wrong that it would give them an investigative advantage, but that’s not the way that liberal societies work. We don’t make things easy for law enforcement agencies because it gives them an efficiency advantage. We make things difficult for them because we only want coercive force in scenarios where it’s absolutely necessary and vital to the public interest.

An interesting counterpoint to Snowden’s remarks came five days later, when a federal appeals court issued its ruling in ACLU v. Clapper. The government often argues that bulk collection is not a “search” until the records are reviewed by human eyes. The court rejected that claim. Although the case was decided on statutory grounds, as Jennifer Daskal wrote afterward, “the holding seems equally applicable to the definition of a search under the Fourth Amendment”:

As the Second Circuit concluded, collection is properly analyzed as a government seizure… [C]ollection matters, even if the subsequent use restrictions are robust and strictly followed. That’s because we have a separate privacy interest not just in how the government uses our data, but in the government’s collection of our data in the first place.

There’s a lot more to take away from our 90-minute conversation, with some of the best questions asked by undergraduate and graduate students in the audience (and one well-informed high school junior). What’s wrong with giving the FBI a “golden key” to every encrypted device as long as it has a court order? Why should anyone be comfortable with a self-appointed insider like Snowden—or a journalistic outsider like me—deciding which secrets to spill? Are his former co-workers “mustache-twirling villains”? If their motives are good, why not trust them? Can free and open source technology, or market forces, reshape the boundaries of surveillance?

The same day, I also gave a panel talk on threats and opportunities for national security journalism. Joining me were Karen Kaiser, the AP’s general counsel, and Matt Olsen, who was chief of the National Counterterrorism Center and, before that, general counsel of the NSA. During the panel, I talked about my experience as one of the journalists who received the Snowden archive. I began by discussing my contorted first conversation at the Washington Post, which, at the time, had a new editor I had never met:

So here was my pitch. I’ve got a national security source. I’ve just learned his name, and I’m not going to tell you yet. He has given me extremely sensitive documents. I’m not saying how many, but they’re more highly classified than anything the Post has ever possessed. There are big and risky stories here, and parts of them I already know I’m unwilling to publish. I’m morally certain that these documents are authentic, but verification will be a bitch.

I can walk you through the first story, but first I need to know that the Post is going to cover my legal bills. Also, you’re going to need a secure room with a heavy safe and air-gapped computers and GPG keys. I feel him holding back a smile, but I just keep going. Don’t worry, I say. I brought a list.

Tune in below to watch the full panel discussion during which I talked about the impact of leak investigations on reporting, the risk of subpoenas, the use of intrusive surveillance against journalists—and even so, why I don’t support a shield law for journalists.

Barton Gellman is a senior fellow at The Century Foundation. In 2013, Gellman was one of three journalists to receive an archive of NSA documents from former intelligence contractor Edward Snowden. In 2014, Gellman led coverage by the Washington Post that shared the Pulitzer Prize for Public Service.