Facebook CEO Mark Zuckerberg testified Tuesday before a joint hearing of the Senate Judiciary and Commerce committees.
The social media company that made Zuckerberg a billionaire many times over is under the microscope for issues relating to data privacy, hate speech, Russian interference in the 2016 presidential election and other security issues.
Here are some sketches of the hearing:
California Sen. Dianne Feinstein seemed to direct her questioning more towards Cambridge Analytica than Facebook.
There have been several times when Zuckerberg has deflected questions that seemed to make him particularly uncomfortable.
Sen. Maria Cantwell (D-Washington) pushed the Facebook CEO on the similarity of the so called "Stanford Analytica," Palantir, to Cambridge Analytica.
Sen. Patrick Leahy (D-Vermont) asked Zuckerberg about the company's responsibility to protect people in Myanmar and about any interaction with special counsel Robert Mueller.
In what started as a moment of levity but quickly drove a point home, Sen. Dick Durbin (D-Illinois) asked Zuckerberg whether he would publicly reveal where he was staying while he was in Washington, D.C.
One surprising moment in the joint Senate and Commerce committee hearing came when Mark Zuckerberg revealed that Facebook has been cooperating with special counsel Robert Mueller's investigation.
Louisiana Senator John Kennedy was very concise in summing up a recurring theme among Senators on both sides of the aisle.
Mark Zuckerberg is scheduled to testify again Wednesday before the House Energy and Commerce Committee.