Cambridge Analytica whistleblower Christopher Wylie talks to Ari Melber ahead of his testimony before Congress. Wylie says he hopes to urge congress that the scandal is beyond the Facebook “a data leak” and could impact “national security”. Wylie reveals work the Trump data firm did for a Russian oil company with ties to Kremlin intelligence, was “concerning” and that they could be aware of a “massive data set being harvested on Americans”.