ATLANTA—A criminal investigation into former President Donald Trump‘s efforts to overturn his election defeat in Georgia has produced a flurry of activity in the last month, with several high-profile witnesses appearing before a special grand jury that is now nearing its end, according to a person familiar with the matter.
While the panel in Atlanta can’t issue indictments, the 23 citizens sitting on it are expected to write a report on their findings, which could include recommendations that indictments be brought. That process could extend into next year, the person said.
Fulton County District Attorney Fani Willis, the Democrat leading the investigation, has prevailed in several court cases brought by Trump allies trying to avoid testifying before the special grand jury. Ms. Willis isn’t expected to issue a subpoena to Mr. Trump for his testimony, however, a possibility she floated earlier in the year.
Michael Flynn, Mr. Trump’s former national security adviser, and Sen. Lindsey Graham (R., S.C.) both appeared before the grand jury in the last month. Rudy Giuliani, a longtime adviser to Mr. Trump, testified this summer. Mr. Trump’s final chief of staff, Mark Meadows, was ordered to testify by South Carolina’s highest court but hasn’t done so.
Messrs. Giuliani, Flynn and Meadows all lost legal fights against the subpoenas in their home-state courts. Some Texas-based witnesses whose testimony Ms. Willis sought haven’t complied after one of them won a state court ruling that she couldn’t be compelled to go to Georgia.
The lengths to which Ms. Willis has gone to speak to members of Mr. Trump’s inner circle suggests that she is closely investigating the former president’s actions, said Clark D. Cunningham, a professor at the Georgia State University College of Law.
“What these witnesses have in common is that they offer, for the district attorney, real potential for tying Donald Trump personally to what happened,” Mr. Cunningham said.
Ms. Willis’s probe is separate from the federal investigations, headed by special counsel Jack Smith, into the handling of classified documents at Mr. Trump’s Mar-a-Lago resort and broader efforts by Mr. Trump and his allies to overturn his 2020 election loss.
The jurors’ report, which can recommend criminal charges or that none be brought, would be reviewed by a panel of Fulton County judges before Ms. Willis’s office decides whether to pursue any charges through a separate grand jury.
Some Georgia lawyers have expressed skepticism about the investigation, saying convening a special grand jury was an unnecessary step designed to maximize publicity for Ms. Willis.
The panel “was a good way to build her national profile and talk to a lot of reporters,” said Andrew Fleischman of the Georgia law firm Sessions & Fleischman, who isn’t involved in the investigation.
Joe Biden beat Mr. Trump in Georgia by about 12,000 votes out of about five million cast, becoming the first Democratic presidential candidate to win the state since 1992. Two statewide recounts and a partial forensic audit, all conducted by the office of Georgia Secretary of State Brad Raffensperger, confirmed President Biden’s narrow victory. Legal challenges to the outcome failed.
Ms. Willis launched the investigation because of a recorded Jan. 2, 2021, phone call in which then President Trump urged Mr. Raffensperger, a Republican and onetime Trump supporter, to find enough votes to overturn his loss. Mr. Raffensperger, who oversees elections in the state, declined to do so.
Mr. Trump, who also spoke on the phone to Mr. Raffensperger’s chief investigator, has said he made “perfect calls” that didn’t violate the law.
The Fulton County probe has expanded to include GOP officials’ creating a slate of presidential electors pledged to Mr. Trump in Georgia, even though he had lost the state. These 16 alternate electors met in December 2020 to sign certificates declaring themselves the state’s legitimate electors.
In court filings, the alternate electors have said they broke no laws. Their goal in signing the certificates, they have said, was to ensure a pathway for Mr. Trump to be declared the winner in Georgia if lawsuits ended up changing the vote count.
Ms. Willis has said in court filings that Republicans involved in the alternate-electors effort are possible targets of her investigation. Securing their cooperation could help her build a case against Mr. Trump and his inner circle, said Mr. Cunningham, the law professor.
The alternate GOP electors included David Shafer, chairman of the Georgia Republican Party, and Burt Jones, Georgia’s lieutenant governor-elect.
Ms. Willis’s investigation hit a snag this summer after she hosted a fundraiser for a fellow Democrat, Charlie Bailey, who ran against Mr. Jones for lieutenant governor.
The fundraiser created the appearance of a conflict of interest, said Fulton County Superior Court Judge Robert McBurney, who oversees the grand jury process. To ensure public trust in the process, he blocked Ms. Willis from developing a case against Mr. Jones or deeming him a target of the investigation.
In addition to the alternate-elector scheme, Ms. Willis has focused on two December 2020 hearings before Georgia lawmakers organized by Mr. Giuliani, a lawyer for Mr. Trump at the time. During those hearings, Mr. Giuliani and allies made unfounded claims about briefcases stuffed with ballots and hacked voting machines.
Ms. Willis informed the former New York City mayor earlier this year that he was a target of her investigation and he testified in August for about six hours. “I can tell you that we were ordered to be here, we showed up, and we did what we had to do,” said Bill Thomas, a lawyer for Mr. Giuliani. Mr. Flynn and his lawyers haven’t commented on his testimony before the panel.
Mr. Graham, who made two phone calls of his own to Mr. Raffensperger in the weeks after the election, testified before the special grand jury for two hours last month. The senator sought unsuccessfully to have the U.S. Supreme Court block his subpoena, arguing that the Constitution’s Speech or Debate Clause protected him as a lawmaker from being questioned about what he said were legislative efforts.
“The senator feels he was treated with respect, professionalism, and courtesy,” Mr. Graham’s office said in a statement about his testimony. “Out of respect for the grand jury process, he will not comment on the substance of the questions.”