AMNA NAWAZ: A judge in New York City today ruled that Donald Trump will go on trial next month to face felony charges that he falsified business records to cover up a sex scandal in order to protect his presidential campaign.

The judge rejected Trump's motion to dismiss or delay the case and told lawyers to prepare for trial starting March 25.

The former president attended the hearing today and again criticized the case against him as politically motivated.

DONALD TRUMP, Former President of the United States (R) and Current U.S. Presidential Candidate: They want to keep me nice and busy so I can't campaign so hard, but maybe we won't have to campaign so hard, because the other side is incompetent.

AMNA NAWAZ: Our William Brangham was in the courtroom this morning, and he joins me now.

So, William, of all the current cases against the former president, this was the oldest.

It's now the first to go to trial, but just remind us, what are the charges that former President Trump is facing here?

WILLIAM BRANGHAM: Let's go back in time, back to 2016.

The presidential campaign is nearing the end, Trump versus Hillary Clinton.

The "Access Hollywood" tape has just come out.

And right around that time, Trump's fixer, Michael Cohen, pays Stormy Daniels, a woman named Stephanie Clifford -- she's a pornographic film actress -- $130,000 to stop her from going public with her story about having a sexual relationship with the married candidate, Donald Trump.

Michael Cohen says that Donald Trump directed him to make that payment.

The election happens, Trump is elected, and he's in the White House.

And then Trump reimburses Michael Cohen that $130,000.

And it is at that point that the Manhattan district attorney, Alvin Bragg, argues that Donald Trump had committed fraud, because he's arguing that he falsified business records to cover up that payment for why he gave that payment in the first place, why he was reimbursing Michael Cohen, and why Michael Cohen was paying Stormy Daniels in the first place.

So, he's charged Trump, Alvin Bragg has charged him with 34 counts of falsifying records.

And he's basically arguing that Trump was trying to hide this fact from voters, and thus was -- this is an election-related crime.

He says that he falsified these records and that that's what's going to be in this case that will be starting soon.

The legal analysts I have spoken to note that these are relatively low-level felony charges that the former president is facing.

And so even if he were convicted of all of them, most of them believe it is very unlikely that the former president would be facing any prison time.

AMNA NAWAZ: So, William, this case in New York was always expected to take a back seat to a federal case down here in Washington on election interference.

So, how did this end up going to trial first?

And what does that mean for the case?

WILLIAM BRANGHAM: Right.

The D.C. January 6 election case being brought by special counsel Jack Smith, that was always supposed to go first.

It was actually going to -- originally scheduled to start in three weeks on March 4.

But former President Trump claimed presidential immunity.

And he appealed this.

The judge overseeing the D.C. case rejected that.

A D.C. appeals court rejected that.

But that appeal is now before the Supreme Court of the United States.

And so in that delay is how this case has now reinserted itself into the schedule.

In fact, today, Judge Merchan, who is overseeing the Stormy Daniels case, noted that he had been in touch with Judge Chutkan, who is overseeing the D.C. case, to talk about the scheduling.

And so he argues that he can now get this hush money case in New York started and completed before the D.C. case would ever begin.

Now, some of the D.C. case is resting on what the Supreme Court does.

If they pick it up, then the D.C. case could be delayed for months.

We just don't really know.

As you played the clip from Trump at the beginning, Trump's lawyers all along were arguing today that it is fundamentally unfair to put Donald Trump on trial for this case right in the middle of the election.

They said he should be out campaigning in states all over the country, not sitting in a courthouse.

But Judge Merchan said, no, justice is not going to wait, and the trial starts March 25.

AMNA NAWAZ: William, I need to ask you about another case.

That's the election interference case in Georgia.

So, the district attorney there, Fani Willis, who's overseeing that case, is now facing allegations of having an improper relationship with one of her lead attorneys.

There was a rather contentious hearing on that today.

What can you tell us about what happened?

WILLIAM BRANGHAM: Amna, I think contentious is the gentlest way to refer to that hearing today.

As you said, the Fulton County district attorney, Fani Willis, is facing these allegations that were brought up by one of the 19 defendants in her huge racketeering election interference case in Georgia.

One of those defendants said, you were having an inappropriate relationship with the lead prosecutor that you selected to run this case, and that, with his salary, he is taking you, Fani Willis, on expensive vacations all over the world and all over the country, and that that's a clear conflict of interest, and you should be disqualified from the case.

So, today, the judge overseeing this, Judge McAfee, held a hearing to try to get to the bottom of this.

And Willis and the lead prosecutor who she was having a relationship with, a man named Nathan Wade, they both admitted, as they had in previous filings, that they did have a relationship, a romantic relationship, but they both reasserted that relationship did not start until after Wade had been hired.

And so the idea that she was intentionally hiring a boyfriend to then reap the benefits of it, they rejected that argument.

There was one witness, a former colleague of Fani Willis, who testified today that she believed the relationship had started many years before, before Wade was hired.

Fani Willis, in later testimony, said that was a former colleague who had been asked to resign because of poor performance, basically implying that she was a disgruntled former employee.

So I want to play just one clip from today.

It was really incredible amount of back-and-forth, conflict with the lawyers, conflict with the judge, Fani Willis herself on the witness stand being -- really pushing back on this.

Let's play this one clip to get a taste of what this was like today.

FANI WILLIS (D), Fulton County, Georgia, District Attorney: You have been intrusive into people's personal lives.

You're confused.

You think I'm on trial.

These people are on trial for trying to steal an election in 2020.

I'm not on trial, no matter how hard you try to put me on trial.

WILLIAM BRANGHAM: So, more testimony will occur tomorrow.

Judge McAfee will decide in the end whether or not Fani Willis has to be removed from this case.

AMNA NAWAZ: All right, that is William Brangham joining us from New York tonight.

William, thank you so much.

WILLIAM BRANGHAM: You're welcome, Amna.