Hey I'm Brian Stelter and welcome to Reliable Sources, our weekly look at the story behind the story.

We're talking about how the media really works, how the news gets made, and how all of us can

help make it better.

And we're starting this hour with political ads pro and con.

Twitter's Jack Dorsey's on one side,

Facebook's Mars Zuckerberg is on the other side,

who's right, who's wrong?

We're gonna get into that.

Plus, Trump fact-checker Daniel Dale is here talking about sometimes

the littlest lies are the most revealing. And we have some never before seen

data about Trump's typos, so many typos. Let's just say he's never going to win one of those spelling bees.

So we have a lot coming up this hour, but our most important story is about the enduring toll of 9-11.

You know, John Stewart recently highlighted the lasting scars of first responders who worked at ground zero.

But did you know that some members of the media are also sick and they are also eligible for health coverage?

We want to get the word out about this, so two journals and they are also eligible for health coverage.

We want to get the word out about this,

so two journalists are going to join me here live,

including the one who shot this video.

They have a critical message for others who covered 9-11.

But let's begin with the most important X-factor in the impeachment fight.

Will right-wing media protect Trump from being convicted and removed from office?

Right now evidence is mounting that Trump abused power and possibly broke the law.

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