Sen. Markey Calls For Greater Protections For Americans' Data Following Facebook, Cambridge Analytica Leak

Wednesday was Day 2 of Mark Zuckerberg's testimony before Congress.

On Tuesday, the Facebook CEO appeared before the joint Senate Judiciary and Commerce Committees. But before the House Energy and Commerce Committee, and the tone was less deferential than in front of the Senate.

Sen. Ed Markey, who represents Massachusetts. He tweets @SenMarkey.