"This case is about a criminal conspiracy," prosecutor Matthew Colangelo began his opening statement in Donald Trump's criminal trial in New York.

"The defendant, Donald Trump, orchestrated a criminal scheme to corrupt the 2016 presidential election," the prosecutor said.

The utterance represents the first time a prosecutor has sought to implicate a former president in a crime at his trial.

Colangelo said Trump schemed with his attorney Michael Cohen and National Enquirer publisher David Pecker "to influence the presidential election by concealing negative information about former President Trump."

Trump slouched in his seat at the defense table, listening.

"The defendant said in his business records that he was paying Cohen for legal services pursuant to a retainer agreement. But those were lies," Colangelo said. "The defendant was paying him back for an illegal payment to Stormy Daniels on the eve of the election."

Donald Trump faced forward and did not appear to make eye contact with any jurors as they entered the courtroom and took their seats in the jury box.

Before any of the lawyers in the case could speak a word, Judge Merchan launched into a lengthy speech outlining how the trial will work.

"We are about to begin the trial of People of the State of New York v. Donald Trump," Merchan told the 12 jurors and six alternates.

Merchan emphasized that the burden of proof rests on the prosecutors and that jurors should presume that Trump is innocent. A guilty verdict requires that each juror determines that the state proved their case beyond a reasonable doubt, Merchan said.

"The defendant is presumed to be innocent," Merchan said. "It is not sufficient to prove that the defendant is probably guilty."

Merchan attempted to set expectations for the jurors, only two of which have ever served on a jury before. For example, Merchan told the jurors not to expect the lawyers to launch into lengthy speeches outside of the opening and closing statements.

"That happens in TV and in movies, but it doesn't happen in real trials," Merchan said.

Judge Juan Merchan ruled that if Trump takes the stand, prosecutors can question him about a number of previous legal issues -- but the judge limited the scope of the cases and the extent to which prosecutors can question him about the facts of those cases.

The ruling is a mixed bag for Trump, who had sought to entirely block questioning on these previous issues if he takes the stand.

Judge Merchan ruled that Trump can be questioned by the DA's office on six determinations from four previous proceedings, including aspects of his New York civil fraud case and the gag order violations there, as well as both verdicts in the E. Jean Carroll cases and the 2018 Trump Foundation case.

Prosecutors had originally asked to question Trump about six different proceedings with 13 total determinations.

Merchan said with his ruling, he has "greatly curtailed" how much prosecutors can discuss the underlying facts of those cases.

"The court cautions the defendant that this Sandoval ruling is a shield, not a sword," Merchan said.

Prosecutors told Judge Merchan that they need 40 minutes for their opening statements.

Defense attorneys told the judge they need 25 minutes.

The judge also announced that court will break at 12:30 p.m. ET today, after a juror had a toothache and got an emergency appointment this afternoon.

Court had already been scheduled to end early today, at 2 p.m. ET, due to the Passover holiday.