Anderson Cooper 360

SOURCES: WH Preparing To Release Whistleblower Complaint As Pelosi Announces Formal Impeachment Inquiry of Pres. Trump; House Speaker Pelosi: "The Actions Taken To Date By The President Have Seriously Violated The Constitution"; Pelosi: President Trump "Must Be Held Accountable, No One Is Above The Law"; Pres. Trump Fires Back At Dems, Calls Formal Impeachment Inquiry "Presidential Harassment!"; Pres. Trump Denounces Impeachment Inquiry As "Witch Hunt Garbage"; Whistleblower's Attorneys: We Applaud The Decision To Release The Complaint; Acting DNI: "I Have Upheld My Responsibility To Follow The Law Every Step Of The Way via Knit