Rules governing attorney conduct apply both inside and out of the courtroom.
“Lawyers definitely have a lot more leeway in press conferences, but they still cannot engage in deceit in their statements,” said Keith Swisher, an ethics law professor at the University of Arizona.
On Twitter and in media appearances, Giuliani and attorney Sidney Powell appeared to have run afoul of rules barring them from making dishonest statements, said Brian Faughnan, a lawyer and ethics specialist in Tennessee.
The Trump campaign has since said that Powell is no longer representing it.
Faughnan said Giuliani acted unethically by tweeting on Nov. 22 that there were “PHANTOM VOTERS” in the Detroit area.
That tweet appeared to reference a sworn statement by a cybersecurity analyst, submitted in court, that had a major error: it confused data from Minnesota with data from Michigan.
Two days previously, the lawyer who filed the affidavit, Lin Wood, conceded that it was mistaken and needed to be corrected.
Giuliani either knew his tweet was false, or reasonably should have known it was false, Faughnan said.