ATLANTA — Days after news broke in January 2021 that President Donald Trump had tried to pressure the Georgia secretary of state to overturn the 2020 election results, Fulton County District Attorney Fani Willis launched a criminal investigation.

Since then, the investigation appears to have dramatically broadened, and investigators have identified more than 100 people of interest as they probe what Trump or his allies did in the weeks after the election. In January, Willis asked a judge to convene a special grand jury that has broad investigative powers. In May, 26 people were chosen to serve.

Here’s what you need to know:

Which actions are under investigation?

Willis and her team appear to have zeroed in on these three areas:

1) Trump’s calls to Georgia’s secretary of state, governor, attorney general and state lawmakers. On top of the Jan. 2, 2021, phone call Trump made to Georgia Secretary of State Brad Raffensperger, R — during which he told the state official to “find 11,780 votes” to change the winner of the presidential election in Georgia — Trump also called Georgia Gov. Brian Kemp, R and Georgia Attorney General Chris Carr, R, in early December 2020 urging them to contest the state’s election results in a special session of the state legislature and at the U.S. Supreme Court, respectively.

The calls to Kemp and Carr came in the lead-up to Georgia’s pivotal dual Senate runoffs and were organized by former Georgia senator David Perdue, R, according to the Atlanta Journal-Constitution. Trump, at the time, also publicly called on state lawmakers and other top officials, including Georgia Lt. Gov. Geoff Duncan, R, to support his campaign’s efforts to contest the results.

2) Testimony that Trump allies gave to Georgia state legislators in December 2020. Trump’s personal lawyer Rudy Giuliani and other senior legal advisers presented now-debunked video to lawmakers purporting to show election fraud at the State Farm Arena in Atlanta, a 2020 voting location. They also cited an outlandish and illegal theory that urged lawmakers to hold a special session of the legislature to select their own slate of electors in defiance of the election results. It is not a crime to falsely testify before a Georgia legislature, according to legal experts, but prosecutors may find that the false comments were knowingly made in bad faith or that they were part of a coordinated effort to delay or overturn the administration of Georgia’s elections.

3) The scheme the Trump campaign coordinated on Dec. 14, 2020, to certify a slate of fake electors to the electoral college to contest the results of the 2020 election. Text messages obtained by The Washington Post show that the Trump campaign and Georgia Republicans knew the plan was baseless and probably illegal.

What are the possible charges?

Legal experts say Trump or his allies might have broken these Georgia laws:

“Solicitation to commit election fraud” is a felony that takes place when anyone pressures a person to, in some way, tamper with election results. Prosecutors are investigating whether Trump credibly broke this law in his phone call with Raffensperger. “The question there, of course, is what was Donald Trump’s intent? Was there the criminal mind necessary to constitute a conviction beyond a reasonable doubt? That’s a tough pill, and there’s a slightly uphill battle,” said Anthony Michael Kreis, a law professor at Georgia State University.

Attempting to “interfere with, hinder, or delay” election administrators’ work is a misdemeanor. That statute, which centers on a person’s actions rather than intent, could cover Trump and his allies’ interference with the secretary of state’s office and local election officials, as well as the Trump campaign’s effort to coordinate a slate of fake electors for the electoral college.

Under Georgia’s anti-racketeering law, it is illegal to coordinate criminal acts through an organization or to do so to gain control of an enterprise. In Trump’s case, the prosecutors could determine that his presidential campaign constituted a criminal enterprise for its conduct after the election or that his team’s coordinated efforts to win the presidency were a conspiracy to take over an enterprise.

The district attorney is in some uncharted territory when it comes to prosecuting cases under these Georgia statutes. There are no reported appellate cases interpreting the election law statutes that prosecutors are likely to scrutinize, while Georgia’s anti-racketeering law was not necessarily intended for cases of election interference.

In 2015, 11 Atlanta educators were convicted on Racketeer Influenced and Corrupt Organizations (RICO) charges for cheating on student standardized tests. Willis was one of the chief prosecutors. That effort underscored both the expansiveness of Georgia’s law, and Willis’s experience in using it in a less traditional way.

“Using Georgia’s RICO law for election fraud crimes is a novel, untested argument, which I think, despite getting tossed around by pundits outside of Georgia, is a highly unrealistic probability,” Kreis said.

It’s also illegal under federal law to “deprive and defraud” people of a “fair and impartially conducted election process.”

What is a special grand jury and why was one called?

Where regular grand juries determine whether to bring criminal charges in a case, a special grand jury has broad investigative powers to find out if organized crime is taking place in its community.

Willis requested a special grand jury because a “significant number of witnesses and prospective witnesses,” including Raffensperger, “have refused to cooperate with the investigation absent a subpoena requiring their testimony,” according to a January letter Willis sent to Fulton County Superior Court Chief Judge Christopher Brasher. Brasher approved the request a week later.

Unlike a normal grand jury, a special grand jury does not vote on whether to bring criminal charges. Instead, it will probably draft a report recommending whether Willis should file charges against Trump or his allies. Should Willis decide to prosecute, a regular grand jury would be called to decide whether to bring charges and in what alleged crimes.

A 23-person special grand jury was seated May 2 and can conduct its work for a year, though Willis has said the body will have completed its investigation long before that. All of the body’s conduct is secret, and prosecutors have made few public remarks about their activities thus far.

Was Willis kicked off part of the investigation?

On July 25, the judge overseeing the case barred Willis and her staff from building a case against one of the Georgia Republicans implicated in the fake-elector scheme, state Sen. Burt Jones, R, who is the Republican nominee for lieutenant governor. Jones won a motion to disqualify Willis because she hosted a fundraiser for his Democratic opponent, Charlie Bailey. A separate district attorney’s office will now oversee Jones’s role in the case.

Who has been subpoenaed?

Prosecutors have said they’ve identified more than 100 people of interest for the special grand jury, while legal analysts have surmised that as many as 50 people could receive subpoenas in the probe. Some of the highest-profile names to have been pursued by investigators include:

Raffensperger, his wife and several of his aides who probably have knowledge of the phone call with Trump.

Georgia House Speaker David Ralston, R, and Duncan, the lieutenant governor, whom Trump’s allies urged to hold a special session of the legislature to contest the election results.

Carr, the attorney general, whom Trump called in 2020 to discuss a Texas legal challenge to Georgia’s elections that Carr called “constitutionally, legally and factually wrong.” Carr testified June 21.

Kemp, the governor, and members of his staff, who were also in contact with Trump in the aftermath of the election. Kemp provided sworn video testimony in late July.

Giuliani, Dallas-based attorney and podcast host Jacki Pick Deason, and Trump campaign attorneys John Eastman and Jenna Ellis, who all testified before Georgia legislators in December 2020 about potential election fraud.

Kenneth Cheseboro, a campaign attorney who drafted at least two memos outlining the fake-elector strategy in Georgia and helped coordinate the event.

Cleta Mitchell, a conservative lawyer who advised Trump and joined his hour-long phone call with Raffensperger.

The 16 Georgia Republicans who participated in the false certification and creation of mock-up documents on Dec. 14, 2020. They include the chair of the Georgia Republican Party, conservative activists, local business leaders and other party officials.

Sen. Lindsey Graham, R-S.C., who had two calls with Raffensperger in November and December 2020 during which he raised questions about Georgia’s mail-in-ballot policies and election administration. Investigators are interested in whether Graham’s conversations were part of Trump’s broader pressure campaign to overturn the election. In February 2021, a spokesperson for Graham said the senator never asked the secretary of state to disqualify a ballot cast by anyone. Graham has been called as a witness, not a potential target of the investigation.

Rep. Jody Hice, R-Ga., who co-signed a Texas legal challenge that sought to overturn Georgia’s election results at the U.S. Supreme Court and introduced a motion objecting to the certification of Georgia’s election results. He was served a subpoena for meetings he had with the Trump White House to coordinate the fake-elector scheme. In late July, a federal judge in Atlanta denied a request from Hice to quash the subpoena.

Will Trump testify?

Trump has not been served a subpoena, though Willis did not rule it out.

“We’ll just have to see where the investigation leads us,” Willis said in a July interview with NBC News. “I think that people thought that we came into this as some kind of game. This is not a game at all.”

Can witnesses avoid testimony?

After Graham was served, his attorneys issued a statement calling the investigation a “fishing expedition” and said the senator would go to court to challenge the subpoena, alleging that any testimony he’d give would be used against Republicans politically. It’s unclear whether a judge would agree to dismiss the subpoena.

Failure to comply with a subpoena would lead to monetary sanctions and potentially imprisonment, though the latter is less likely.

Duncan, the lieutenant governor, and several members of Georgia’s General Assembly argued that the special grand jury could not ask them to testify, citing legislative immunity. In July, Fulton Superior Court Judge Robert McBurney ruled that Duncan and former state senator William Ligon, R, will have to testify, though the judge will set up a “framework” for what questions investigators are allowed to ask them and other state legislators.

What has been Trump’s response to the probe?

Trump has responded to this investigation the same way he has others scrutinizing him or those close to him, calling it a “witch hunt.”

“The young, ambitious, Radical Left Democrat ‘Prosecutor’ from Georgia, who is presiding over one of the most Crime Ridden and Corrupt places in the USA, Fulton County, has put together a Grand Jury to investigate an absolutely ‘PERFECT’ phone call to the Secretary of State,” Trump wrote in a May 31 post on his social network, Truth Social.

Trump has doubled down on his false claims of a stolen election. “I called to fight a Rigged & Stolen Election, and they go after me instead of the people that Rigged and Stole it. God Bless America!” he wrote.

In January 2021, shortly after Willis launched the inquiry, her office requested security aid from the FBI after Trump called for “the biggest protests we’ve ever had” in cities across the country where he’s being investigated.

What other investigations into Trump are underway?

The Fulton County investigation is far from the only inquiry into Trump’s conduct around the 2020 election or his various business enterprises. There are several investigations at the federal, state and local levels ensnaring Trump’s various business and political enterprises that may bring material legal consequences for the former president.

They include investigations into the Trump Organization’s business practices by the New York attorney general and Manhattan district attorney; the tax records of Trump’s golf club in Westchester, N.Y., by the Westchester district attorney; the use of nonprofit funds by the Trump Organization, Trump International Hotel and the former president’s inaugural committee by the D.C. attorney general; and several interlocking investigations by the Justice Department about the Trump White House’s activities surrounding Jan. 6.

The Justice Department is investigating Trump’s actions as part of a criminal probe, sources tell The Post. The congressional committee investigating the Jan. 6 Capitol attack is also squarely interested in Trump’s conduct before and after the riot.