Sources: Second whistleblower has first-hand knowledge of Ukraine events

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A second whistleblower has come forward with information regarding the Ukraine call at the center of the impeachment inquiry into President Trump. According to legal sources, the second whistleblower "has first-hand knowledge" of the events. NBC's Hans Nichols explains how this undercuts the "hearsay" argument coming from the White House in an attempt to discredit the first whistleblower.