It started with a telephone call.
Shortly after Donald Trump's extraordinary Jan. 2, 2021 conversation with Georgia Secretary of State Brad Raffensperger went viral, Atlanta-area District Attorney Fani Willis launched a far-reaching criminal investigation into interference in the 2020 election that now stands at a crucial inflection point.
Here is what we know:
Big hearing: On Tuesday, a Fulton County Georgia judge is set to consider whether the findings of a special grand jury's months-long investigation, including any recommendations related to the possible prosecution of the former president and his allies, should be made public.
Imminent threat to Trump: Analysts have characterized the inquiry as perhaps the most serious legal threat facing the former president.
Top Trump aides in crosshairs: Trump attorney Rudy Giuliani, designated as a target in the inquiry, headlined a list of former aides and allies of the former president summoned to testify before the panel.
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Trump call to Raffensperger led to wider investigation
While the inquiry started with Trump's call to Raffensperger, in which the former president urged Georgia's top election official to "find 11,780 votes" to tilt the 2020 statewide election in his favor, the inquiry has since expanded to include a wide-ranging examination of election fraud.
Specifically, Willis has said authorities have been investigating possible election fraud, conspiracy, oath of office violations, racketeering and election-related violence.
In addition to Guiliani, prosecutors have designated nearly two-dozen others, including a group of Republican electors who falsely certified that Trump had won the election, as potential targets.
Witnesses include Trump allies Lindsey Graham, Michael Flynn and John Eastman
The list of grand jury witnesses included current and former public officials, many who have been part of Trump's inner-circle.
Sen. Lindsey Graham, R-S.C., who was summoned for questions about his contacts with Georgia election officials.
Former Trump national security adviser Michael Flynn, a vocal proponent of false claims of election fraud
Trump lawyer John Eastman, who helped develop Trump’s strategy to overturn Biden's presidential election victory.
Other prominent witnesses have included Raffensperger and Georgia Gov. Brian Kemp, both of whom resisted Trump's pressure campaign to overturn Biden's statewide victory.
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What to expect Tuesday
Special grand juries, like the one seated in the election inquiry, do not have authority to make charging decisions. Instead, the panel issues a report and recommendations to the district attorney for action.
Fulton County Superior Court Judge Robert McBurney, who disclosed last week that the jury had completed its work and forwarded its report, also indicated the panel had "voted to recommend that its report be published."
The hearing will determine whether there any objections or other considerations to weigh before taking action.
The hearing could result in the full release of the report and the panel's recommendations, a partial disclosure or a decision to withhold the document pending any decision on prosecution.
Trump's Georgia lawyers said Monday that they will not take part in the session.
"To date, we have never been a part of this process," attorneys Drew Findling and Marissa Goldberg said in a written statement, adding they believed the former president would not be charged.
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What could Fani Willis do?
Willis is not obligated to act on the grand jury's recommendations. If she does elect to proceed, the prosecutor would likely present a case to one of the county's two regular grand juries to seek indictments.
The district attorney had expected to make decisions on possible charges before the end of 2022, but a number of legal challenges pressed by key grand jury witnesses pushed late into the year.
A Brookings Institution analysis of the Willis investigation, co-authored by Norm Eisen, a special counsel to the House Judiciary Committee during Trump's first impeachment, concluded that the inquiry represents perhaps the most serious threat to Trump.
"We conclude that Trump is at substantial risk of criminal prosecution in Fulton County (Georgia)," the report found.
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This article originally appeared on USA TODAY: Trump Georgia investigation: Judge to consider release of report