The complaints about Facebook have also helped propel debate about the technology industry more widely, and whether the biggest technology companies — like Facebook, Google and Amazon — have grown too large and powerful. Some lawmakers are now talking about potential ways to regulate the businesses.
In addition to the new crisis communications firms, the company has placed ads in places like The New York Times and The Washington Post. But it has been difficult to quell the concerns of lawmakers, and Ms. Sandberg’s meetings this week were focused on fixing various problems facing the company.
Ms. Sandberg, 48, knows her way in Washington, having worked here for years as a top aide in the Treasury Department. She is now regularly mentioned as a potential political candidate. That speculation increased in 2013 after the release of her first book, “Lean In: Women, Work, and the Will to Lead.” She was a vocal supporter of Hillary Clinton in the 2016 election and is a top Democratic donor.
She has tried to deflect rumors about running for office, but they persist, and her appearance in Washington this week is unlikely to quell them. At her only public event in Washington, she gave smooth and measured answers to questions from Mike Allen, a co-founder of Axios, the online news start-up that hosted the event. The performance stood in stark contrast to efforts from Mr. Zuckerberg, the Facebook founder and chief executive, who usually appears far less comfortable in such situations — and who has also been mentioned as a potential political candidate.
With House Intelligence Committee leaders who are investigating the company’s role in foreign meddling in the election, Ms. Sandberg agreed to hand over a broader set of data linked to fake Russian accounts and to give more information about how that data was targeted to users. With top Republican and Democratic leaders of the House, she emphasized the company’s desire to help with the investigation and promoted its plan to hire thousands of people to review ad purchases so the mistakes of the 2016 election are prevented from happening again.
“They are leaning in on this issue,” said Representative K. Michael Conaway of Texas, the Republican leading the Intelligence Committee’s investigation, alluding to Ms. Sandberg’s book.
“They have launched a platform that communicates around the world,” Mr. Conaway said, “and it’s important for us to understand their perspective.”
In a one-hour meeting Thursday with at least 17 members of the Congressional Black Caucus, Ms. Sandberg delivered the same message and a peace offering.
The members have been critical of Facebook’s lack of diversity on its board of directors, and lawmakers have criticized the company for allowing racially charged ads on its site during the election that were placed by the Russian accounts under review in the federal investigation. Sitting at a large wood conference table with the House members of the caucus, she listened to complaints and questions while taking notes.
Ms. Sandberg responded with personal reflections. She said she was disappointed that Facebook ads had been used to sow racial division during the election, according to the caucus chairman, Representative Cedric L. Richmond, a Democrat from Louisiana. She told the caucus that she prayed daily that Facebook hadn’t contributed to the outcome of the election, according to Representative G. K. Butterfield, a Democrat from North Carolina. And she promised that Facebook would appoint an African-American member to its board in the near future.
“I remain cautiously optimistic,” Mr. Butterfield said after the meeting.
A group of Facebook executives, including Elliot Schrage and Anne Kornblut, traveled with her from the company’s headquarters in Menlo Park, Calif. The Axios event was filled with Facebook lobbyists including Joel Kaplan, who had been running damage control with Republicans in government, and Erin Egan, a top policy executive.
After the meeting with members of the Congressional Black Caucus, one of her last events of the tour, Ms. Sandberg walked past dozens of reporters with smartphones pointed at her and asking questions. Accompanied by Ms. Egan and the company’s chief diversity officer, Maxine Williams, she walked up the marble steps of the Capitol to the white-carpet offices of the House minority leader, Representative Nancy Pelosi of California, where she put her big, black satchel in an empty conference room as she typed into her smartphone.
When asked to comment on her day, Ms. Sandberg waved her hands and said: “Sorry, we’re not talking. I need time for myself.”