http://www.washingtonpost.com/blogs/the-switch/wp/2018/03/22/a-key-congressional-committee-has-asked-facebook-ceo-mark-zuckerberg-to-testify-on-cambridge-analytica/

Congressional lawmakers have formally requested that Facebook chief executive Mark Zuckerberg testify at an upcoming hearing in response to reports that a data analytics firm used by the Trump campaign had improperly accessed the names, "likes" and other personal information of about 50 million users on the social site.

The request officially came Thursday from the House Energy and Commerce Committee, a powerful panel that oversees Facebook and its tech peers, and arrives a day after Zuckerberg said he would be "happy" to appear on Capitol Hill to address lawmakers' lingering questions about Facebook's privacy protections.