Two years ago, Jack M. Balkin, a constitutional-law professor at Yale, published a fifty-page article in the U.C. Davis Law Review examining what he called problems “at the intersection of information privacy and the First Amendment.” On one hand, he noted, people want to protect private information. On the other, information businesses tend to challenge regulation as infringements of free speech. Balkin ran through some prospective solutions. The government could regulate the collection and use of information, or the time, place, and manner of expression. Companies could treat data as commercial speech, or as a commodity. Platforms could make privacy contracts with their users. Yet Balkin found all these options lacking. Instead, he offered the idea of the “information fiduciary.” Fiduciaries, in traditional contexts, are defined by two responsibilities. They must be loyal to their clients’ interests, and they must show a “duty of care.”

It was no surprise to find Balkin’s article mentioned during Mark Zuckerberg’s testimony to the Senate Judiciary and Commerce Committees earlier this week. To a striking degree, the fiduciary model was the one toward which discussion slowly and chaotically converged. The hearing revealed little about Facebook, the company that Zuckerberg founded, and a lot about the committees, which at times seemed hair-raisingly ill-equipped for their task. Senators used chunks of their speaking time for basic, F.A.Q.-type queries about the platform; many seemed so unversed that they couldn’t rephrase their own questions. Hiding within this general haze, though, was a specific ambiguity, about Facebook’s data policy. “You own the information you share on Facebook,” the site’s privacy principles state. “This means you decide what you share and who you share it with.” Usually, committee members pointed out, ownership means more.

Some noted that users lack a financial stake in the information that they supposedly own. “You’re making about forty billion bucks a year, and I’m not making any money—it feels as if you own the data,” Senator Jon Tester, of Montana, told Zuckerberg. Users have no way of protecting their data against theft, Tester added, and no recourse if a breach happens. “If I own it, I can stop it,” he said. Senator Richard Blumenthal, of Connecticut, asked whether Zuckerberg would agree to an opt-in standard of privacy, which seeks users’ affirmative consent, rather than the current opt-out model. “I think that certainly makes sense to discuss,” Zuckerberg told Blumenthal. It’s the sort of thing that people say to strangers who are being boring at parties.

Yesterday, Zuckerberg continued his Capitol Hill tour before the House’s Committee on Energy and Commerce. This was a better showing on the part of lawmakers—the House members, whether as a function of relative youth or relative thirst or both, behaved less like dogs shaking off an afternoon nap—and a harder one for Zuckerberg. Questions about data ownership intensified. “To me, if you own something, you ought to have a say about how and when it’s used,” Representative Doris Matsui, of California, said. Representative Ben Luján, of New Mexico, questioned the ownership idea by pointing to Facebook’s activities on the greater Web. “You’re collecting data on people that are not even Facebook users, that have never signed a privacy agreement!” he said. How could those people own their information in any meaningful sense? (Zuckerberg previously confirmed that the company has acquired non-user data.) To these lawmakers, information ownership seemed a sort of cosmetic abstraction: Facebook did its profit-generating work with individuals’ data whether terms of ownership existed or not.

What, then, did they seek as an alternative standard of protection? With scores of lawmakers parading all sorts of ideas through nearly ten hours of hearings, it was not always easy to tell, but slowly something like a pattern emerged. What members of Congress wanted from Facebook was accountability to users’ privacy interests no matter who owned what, and no matter how much users understood—a duty of care. Over and over, trying to articulate their hopes, they fell back on a general term to describe a specific sort of ideal user experience. The word they used was “trust.”

The Latin word for trust is “fiducia.” In 2016, to demonstrate the legal specialness of a fiduciary relationship, Balkin imagined a daytime gynecologist who, in his or her nighttime life, creates an artwork from patients’ photos and case files. Is that work protected by the First Amendment, as other art would be? Balkin believes not. “You are using sensitive information to your advantage and to the disadvantage of your patients,” he wrote—a breach of the relationship. Doctors and lawyers are information fiduciaries because they hold in confidence data about us, whether it’s supplied or gathered. By these and related standards, certain types of digital platforms—such as Facebook—can be seen to have fiduciary duties, too.

On his popular legal blog last month, Balkin suggested that Zuckerberg already leaned toward a fiduciary notion of his company’s data responsibilities. (He found the evidence, he thought, in Zuckerberg’s posted response to the Cambridge Analytica scandal.) If so, Zuckerberg seems to have been brainwashed of that position before arriving on Capitol Hill this week. One of his most revealing replies—a bar not hard to clear, given how little he said—came during questioning by Representative Scott Peters, of California, who posited a misalignment between Zuckerberg’s personal values and his duties to shareholders. Zuckerberg balked. “I think a lot of these hard decisions come down to different interests between different people,” he said. “On the one hand, people want the ability to sign into apps and bring some of their information and bring some of their friends’ information in order to have a social experience. On the other hand, everyone wants their information locked down and private.”

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In other words, it’s not our fault; it’s your confusion. That isn’t fiduciary talk. “Tort and fiduciary law assume that professionals and their clients do not stand on an equal footing,” Balkin explained in his Review article. “Professionals have special skill and knowledge that clients often lack. Clients are usually dependent on professionals to perform important tasks for them.” Over and over again this week, Congress flogged a version of this point, focussing on the inscrutable legalese in Facebook’s documents. “Your user agreement sucks,” Senator John Kennedy, of Louisiana, said on Tuesday. “Do you think the average consumer understands what they’re signing up for?” Senator Lindsey Graham, of South Carolina, asked. To the extent that Facebook grasped the nuances of information collection and use, they seemed to suggest, it had a responsibility to protect users from the effects of their own incomprehension. (It was Senator Brian Schatz, of Hawaii, who explicitly connected this idea with Balkin’s work, to which Zuckerberg issued another cocktail-party reply: “Jack is very thoughtful in this space.”)