Facebook CEO Mark Zuckerberg leaves a meeting with Sen. Bill Nelson, D-Fla., the ranking member of the Senate Commerce Committee, on Capitol Hill in Washington, Monday, April 9, 2018. Zuckerberg will testify Tuesday before a joint hearing of the Commerce and Judiciary Committees about the use of Facebook data to target American voters in the 2016 election. (AP Photo/J. Scott Applewhite)