Welcome to the investigation. I'm Chris Vlasto Senior Executive Producer here at ABC News. I'm joined by my colleague John Santucci in Washington.

Today we're joined by former Homeland Security Advisor and ABC News consultant, Tom Bossert. Well, Tom, listen, about a month ago or so,

you were one of the first people to come forward

and really say to the president

that he was being ill-served by Rudy Giuliani.

Let's listen to what you said.

The whistleblowers complain says

that White House officials were deeply disturbed

by the president's phone call with Zelensky. What was your reaction? Yeah, I'm deeply disturbed by it as

well. And this entire mess has me frustrated, George. Thanks for having me on. You and I both live

through the impeachment of President Clinton and saw how frustrating and dividing it can be. And I've just

spent the week overseas. And I've just spent a week overseas,

and I'll tell you, the whole world is watching this.

The removal of a president is a big and serious deal.

But the removal of a president in not only a democracy,

but the biggest democracy in the world is really a weighty matter,

and I hope that everyone can sift through the evidence

and be very careful, as I've seen a lot of rush to judgment this week.

That said, it is a bad day and a bad week for this president and for this country if he is

asking for political dirt on an opponent.

Now, what the president is referring to there is a debunked conspiracy theory that somehow Ukraine,

not Russia, hacked the Democratic emails in 2016, and that Ukraine might have the DNC server

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