But in 2010, in an effort to help regulators keep current with rapid advances in technology — and understand the possible risks to consumers of novel uses of their data — the agency created the position of chief technologist. And in just a few years, it has established a tradition of appointing gadflies to the post, experts who have poked holes in companies’ assurances that they were keeping the public’s personal details safe and private.

The commission first tapped Edward W. Felten, a computer science professor at Princeton, to serve as chief technologist; he came to the agency after discovering security flaws in voting machines that hackers could have exploited to steal votes. More recently, Latanya Sweeney, a professor of government and technology at Harvard, served in the role; she famously demonstrated that it was possible to reidentify patients by name in the nameless medical records that hospitals routinely released to researchers.

Image Mr. Soltani's appointment, announced by Edith Ramirez, the F.T.C.’s chairwoman, drew criticism from an online-advertising trade group. Credit... Susan Walsh/Associated Press

Mr. Soltani’s worldview is similar to his predecessors’, but his résumé is different. At 40, he is younger and does not have their Ivy League affiliations. He is a populist who has conducted research into online consumer tracking and profiling for several national newspapers and government agencies.

In 2014, he was part of a team at The Washington Post that won a Pulitzer Prize in public service for a series of articles examining government surveillance techniques brought to light by the former National Security Agency contractor Edward J. Snowden. (He has also worked as a researcher at The New York Times and provided technical assistance for the newspaper’s “You for Sale” series on the data brokerage industry.)

Along the way, Mr. Soltani has earned a reputation as a forensic specialist able to explain complicated technical processes in plain terms that policy makers and ordinary souls can understand.

“If the store you went into tracked everything you tried on and touched and then followed you to other stores, and the stores would all exchange notes, I think people would be uncomfortable with that and stop shopping,” Mr. Soltani said at the conference in Philadelphia. “But that is exactly what happens online.”