Judge Merchan then reviewed each of the counts against Trump to explain the People's burden of proof.

He said that in the interest of brevity, he would instruct them on Falsification of Business Records for the first count -- but not the full instruction for all 34 counts, because they are identical.

Merchan methodically walked through each of the allegedly falsified documents, listing the dates, voucher numbers, and check numbers for each of the records.

The judge said he would be happy to repeat the instructions later if the jury so requests.

Judge Merchan explained to jurors the prosecution's three theories for the unlawful means used to influence the 2016 election.

First, Merchan said that the unlawful means could include a violation of the Federal Election Campaign Act, which caps campaign contributions. Prosecutors allege that Michael Cohen's payment to Stormy Daniels exceeded the legal cap.

Second, Merchan said prosecutors argue that Trump and others falsified business records, including the bank paperwork for Essential Consultants Inc., the money wire to Daniels, and the 1099 forms related to Cohen's repayment.

Third, Merchan said the crime could be violations of tax laws related to the "grossing up" of Cohen's reimbursement to cover the taxes he would owe on the payment.

Judge Merchan tells the jury that prosecutors allege that Trump attempted to conceal a violation of New York election law by falsifying business records.

"They need not prove that the other crime was committed, aided, or concealed," Merchan said.

Prosecutors are relying on New York Election Law 17-152, which prohibits "any two or more persons who conspire to promote or prevent the election of any person to a public office by unlawful means." Prosecutors offered three theories of the "unlawful means" mentioned in that law.

Though jurors will need to agree Trump falsified records in furtherance of an additional crime in order to convict, "they need not be unanimous" on "what unlawful means" were used, Merchan said.

Judge Merchan instructed the jury about how to decipher intent, telling them it "does not require premeditation."

Intent can even be momentary, Merchan said, telling the jurors the question about how to judge intent "naturally arises."

"You must decide if the required intent can be inferred beyond a reasonable doubt," he told them.

Merchan also said earlier, "If it is proven the defendant is criminally liable for the conduct of another, the extent or degree of defendant's participation does not matter ... The defendant is as guilty of the crime as if he had personally omitted the crime."

Prosecutor Josh Steinglass rehashed the phone call that then-National Enquirer publisher David Pecker said he had with Trump about the Karen McDougal payment.

During the phone call, Pecker testified that Trump expressed skepticism about the hush money payment.

"Mr. Trump said to me ... 'I don't buy stories.' And he said, 'Anything you do anything like this, it always gets out,'" Pecker testified.

"He thought that these stories always get out and I guess he was right about that," Steinglass told jurors.

"Their motivation was to serve the campaign -- that's what makes this a catch-and-kill" the prosecutor said.

Michael Cohen was Trump's "liaison" to Pecker, "conveying Mr. Trump's instructions every step of the way," Steinglass said.

"Critical here is Pecker's acknowledgement that he never intended to publish the story under any circumstances … Pecker was willing to sacrifice AMI's bottom line in service of the campaign," said Steinglass, emphasizing that that AMI's $150,000 payment to Karen McDougal was not standard operating procedure for the National Enquirer.

Steinglass told jurors that Pecker thought the story, if true, was "National Enquirer gold" -- yet he would not have run the story to help Trump.

"Pecker was willing to sacrifice AMI's bottom line in service of Donald Trump's campaign," Steinglass said. "This deal was the very antithesis of a normal press function."