During the hearing before the Senate Judiciary and Commerce committees Tuesday afternoon, Facebook CEO Mark Zuckerberg wasn’t interested in sharing any personal information about who he had privately messaged this week, when asked.

Sen. Dick Durbin (D-IL) asked Zuckerberg, “Would you be comfortable sharing with us the name of the hotel you stayed in last night?”

Zuckerberg, stunned, stuttered, “Uh…. no!”

Durbin hit back again, “If you’ve messaged anybody this week, would you share with us the names of the people you’ve messaged?”

Zuckerberg stuttered again, “Senator, no, I would probably not choose to do that publicly here.”

“I think that might be what this is all about,” Durbin responded. “Your right to privacy, the limits of your right to privacy, and how much you give away in modern America, in the name of ‘connecting people around the world.'”

“The question basically of what information Facebook is collecting, who they’re sending it to, and whether they were asked in advance for permission to do that… is that a fair thing for a user of Facebook to expect?” Durbin asked him.

Watch the exchange below.