Mark Zuckerberg will be added to a Facebook privacy lawsuit.

WASHINGTON — The attorney general for the District of Columbia on Wednesday added Facebook’s chief executive, Mark Zuckerberg, to a consumer protection lawsuit, in one of the first efforts by a regulator to expose him personally to potential financial and other penalties. The attorney general, Karl Racine, said that continuing interviews and reviews of internal documents for the case had revealed that Mr. Zuckerberg played a much more active role in key decisions than prosecutors had known.

Facebook is at the center of multiple legal battles with regulators. It is the target of antitrust and consumer protection lawsuits by the Federal Trade Commission and several state attorneys general.

Regulatory pressure is also mounting. U.S. lawmakers are introducing bills to regulate social media companies and technologies that spread harmful content. On Wednesday, Senator Richard Blumenthal of Connecticut wrote Mr. Zuckerberg asking him to testify in a hearing on Instagram’s harms to teenagers. Also on Wednesday, Britain’s antitrust authority fined Facebook $70 million for breaching reporting rules related to an investigation of the company’s acquisition of Giphy.

None of those actions have directly addressed the role played by Mr. Zuckerberg, who has more than 50 percent control of voting shares. But Mr. Racine’s move could result in large financial penalties for Mr. Zuckerberg. The District of Columbia could can seek up to $5,000 for any of the district’s 300,000 residents who may have been affected by the Cambridge Analytica data privacy violation.

“This is a power move and gets to the problem,” said David Vladeck, a professor of law at Georgetown and the former head of consumer protection at the F.T.C. “Facebook is very unusual because of its corporate structure that makes Mark Zuckerberg the ultimate decider on all important decisions.”

Mr. Racine’s complaint against Facebook was filed in December 2018 in the Superior Court of the District of Columbia. The suit charges that Facebook misled consumers about privacy on the platform by allowing Cambridge Analytica, a political consulting firm, to obtain sensitive data from more than 87 million users, including more than half the district’s residents.