Departing court after the first day of the trial, Rudy Giuliani told ABC News' Terry Moran that he has no regrets about his treatment of Ruby Freeman and Shaye Moss -- and he doubled down on his core allegations about them.

"When I testify, the whole story will be definitively clear that what I said was true, and that, whatever happened to them -- which is unfortunate about other people overreacting -- everything I said about them is true," Giuliani told reporters.

"Do you regret what you did to Ruby and Shaye?" Moran asked.

"Of course I don't regret it," Giuliani said. "I told the truth. They were engaged in changing votes."

"There's no proof of that," Moran responded.

"You're damn right there is," Giuliani retorted. "Stay tuned."

Court will resume Tuesday at 9 a.m. ET.

Plaintiffs' first witness in the case is a social media monitor who testified about the deluge of "racist and graphic material" targeting Freeman and Moss that appeared online after Giuliani began accusing them by name.

Regina Scott, a retired Chicago Police Department official who now works as a security and risk analyst, testified that negative mentions about Freeman and Moss surfaced online at a prodigious rate.

A report Scott prepared identified more than 710,000 mentions of Freeman and Moss between November 2020 and May 2023, and 320,000 mentions between Aug. 18, 2023, and Nov. 11, 2023.

"The type of violent and racist and graphic material, that's on a level we don't see at all in our work," Scott said.

-ABC News' Laura Romero

Joseph Sibley, an attorney for Rudy Giuliani, implored jurors to withhold judgment of his client and consider a "fair and proportionate" monetary penalty when the trial concludes, framing the $43 million sought by Freeman and Moss as a "truly incredible" figure.

"What the plaintiffs' counsel are asking for in this case is the civil equivalent of a death penalty," Sibley told jurors in brief opening remarks.

Sibley, in making his case to the jury, ceding before arguments even began that Giuliani made defamatory comments about Freeman and Moss -- but he refuted the notion that his comments led to the abuse that followed.

"There's really no question that these plaintiffs were harmed," Sibley said. "They're good people, they didn't deserve what happened to them."

But Sibley urged jurors to consider only "what can actually be attributed to Mr. Giuliani."

"He never promoted violence against these women, never made racist statements about them," Sibley said of Giuliani. "That was other random people."

Ruby Freeman and Shaye Moss suffered a "perpetual nightmare," their attorney Michael Gottlieb told the jury during his opening remarks, saying that the damage they suffered warrants an "award in the tens of millions of dollars."

Gottlieb told jurors his clients suffered three types of damages -- reputation, emotional and punitive -- due to Giuliani's "defamation campaign."

In addition to the costs to "repair their reputation," Gottlieb told jurors that Freeman and Moss' award should account for lost wages, forced relocation, security expenses, and more.

-ABC News' Laura Romero

The parties have selected a jury of eight D.C. residents, and attorneys for both sides are expected to present their opening statements this afternoon.

Giuliani has said that, while he "does not contest the factual allegations" made by Freeman and Moss regarding his statements, the statements themselves were constitutionally protected.

Attorneys for Freeman and Moss will attempt to articulate why their clients deserve monetary compensation for the statements Giuliani made about them, including what they say is his willful infliction of emotional distress and reputational harm.

Judge Howell swore in the jury and excused the remainder of the prospective jurors before breaking court for lunch.