Trump trial: Biden calls Trump's remarks 'dangerous'

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."

Judge Merchan told jurors that Michael Cohen is an "accomplice" to the alleged crime, so the jury cannot convict Trump on Cohen's testimony alone.

Even if they believe Michael Cohen, they need to rely on evidence corroborating his testimony, Merchan said.

Trump, at the defense table, appeared to perk up just a bit at this, looking up at Merchan as he delivered this information to the jury.

Judge Merchan told the jury that they have the ultimate authority in determining the truthfulness of a witness' testimony -- an instruction that might come in handy given the emphasis that defense lawyers placed on Michael Cohen's testimony, which they say includes lies.

"You will alone determine the truthfully and the accuracy of the testimony of each witness," Merchan said.

He added that the jury could either disregard the testimony of an untruthful witness entirely, or disregard part of it.

"There is no particular formula" to determine credibility, Merchan said.

"You may consider whether the witness has any interest in the outcome of the case," he said -- another matter that might weigh on jurors' minds.

"You may consider whether a witness did have, or did not have, a motive to lie," the judge said.

Trump's attorney had told the jury Cohen had an "axe to grind" against his former boss. Prosecutors partially conceded that Cohen had a motive, acknowledging that, to date, he is the only one who suffered any consequences from the matter at hand.

Trump, at the defense table, appeared to look over to the jury and offer a bit of a closed-mouth grin.