Welcome to The Investigation. I'm John Santucci, senior editorial producer here at ABC News and your podcast co-host.

I'm joined by Terry Moran, Senior National Correspondent and Catherine Fultor's Capitol Hill and White House reporter.

We were supposed to have a busy week in Washington coming into another round of depositions,

but that did not happen after the White House won a battle blocking several key allies of President Trump

from going up to comply with a congressional request for their closed-door depositions.

So, Catherine, what do we know right now?

Because these four individuals that were supposed to start, what's already going to be another busy week up on Capitol Hill,

they would have been quite significant to the Democrats' investigation into President Trump.

Yeah, and that's exactly how Chairman Schiff described it when he spoke to reporters following,

finding out that they wouldn't show up.

I think John Eisenberg, he's one of the White House lawyers.

He's very significant here because, as we've reported, he's one of those who was actually responsible

for moving the transcript and the notes from the president's call with the president of Ukraine

to that secret classified server. The others were OMB, Office of Management and Budget officials

who would have a direct window into what happened with that aid being held up to Ukraine. Schiff

and other Democratic members describe these people as

key witnesses. But I think important to note here, and when we asked Chairman Schiff about this,

he said that the White House blocking these people directing them not to come isn't going to

hold up their work. They're still moving ahead, and it could potentially lead to

an article of impeachment that is obstructing their investigation, their impeachment investigation.

Now, the one other person that would have, in theory, booked Mark the end of this week, is former

National Security Advisor John Bolton. He obviously would be fascinating in this investigation

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