While investigations of former President Donald Trump in New York and on Capitol Hill have monopolized the attention, it’s the probe launched last year in Fulton County that’s seen by some legal experts as the most potentially damaging to the ex-commander-in-chief.

Since Fulton District Attorney Fani Willis announced her inquiry, it’s become clear she’s looking at several episodes that occurred in Georgia in the two months following the 2020 presidential elections.

They include: phone calls placed to state officials from Trump or his allies; the appointment of a slate of “alternate” GOP electors; leadership changes in the Atlanta U.S. Attorney’s office; legislative hearings that featured falsehood-filled testimony from Trump’s personal attorney, Rudy Giuliani; a breach of elections data in Coffee County; and efforts to pressure a Fulton County poll worker.

Here are the key developments so far:

Jan. 1, 2021

Veteran prosecutor Fani Willis is sworn in as Fulton County’s district attorney, becoming the first woman to hold the job. She had punched her ticket months earlier by soundly defeating her one-time boss, the six-term incumbent Paul Howard, in the Democratic primary runoff.

Jan. 2, 2021

Then-President Donald Trump, scrambling to challenge election results in several swing states, calls Georgia Secretary of State Brad Raffensperger. During the leaked hourlong conversation, Trump urges Raffensperger to “find” the nearly 12,000 votes to reverse his narrow defeat in Georgia.

Feb. 10, 2021

Willis announces her office is launching a criminal investigation into alleged attempts by Trump to change the outcome of the 2020 election in Georgia. She urges Raffensperger and others the president contacted, including Gov. Brian Kemp and Attorney General Chris Carr, to preserve documents that could be relevant to the probe.

She said the investigation includes but is not limited to “potential violations of Georgia law prohibiting the solicitation of election fraud, the making of false statements to state and local governmental bodies, conspiracy, racketeering, violation of oath of office and any involvement in violence or threats related to the election’s administration.”

Willis said her office is best suited to handle the investigation since all of the state’s other investigative agencies with jurisdiction, including the secretary of state and attorney general’s offices, have conflicts because their leaders had been contacted by Trump.

Jan. 20, 2022

Willis requests a special purpose grand jury to aid in her investigation of Trump. She tells members of Fulton County’s Superior Court that a “significant number of witnesses and prospective witnesses have refused to cooperate with the investigation absent a subpoena requiring their testimony,” singling out Raffensperger. Willis later told the AJC that at least 30 people had declined to testify without a subpoena.

Jan. 24, 2022

A majority of the judges on the Fulton County Superior Court bench greenlight Willis’ request for a special purpose grand jury, which can meet for a period “not to exceed 12 months.” Judge Robert McBurney is assigned to supervise the jury and receive its reports.

Jan. 29, 2022

During a rally in Conroe, Texas, Trump tells supporters to launch “the biggest protest we have ever had” in Atlanta, New York and Washington, D.C., if prosecutors “do anything illegal” in their probes of his activities. Trump also called prosecutors “radical” and “racist.” The top investigators leading the four major investigations are Black.

Jan. 30, 2022

Willis asks the head of the FBI’s Atlanta field office to conduct a risk assessment of the Fulton County Courthouse and Government Center and provide other protective resources, such as federal agents and intelligence. She says that security concerns were “escalated” by comments Trump made and that she wants to deter a Jan. 6-style insurrection.

May 2, 2022

McBurney selects 23 Fulton County residents, as well as three alternates, to sit on the special grand jury out of a pool of 200 people.

June 2, 2022

Secretary of State Brad Raffensperger and his wife, Tricia, become the first two witnesses to testify before the special grand jury.

Early summer, 2022

Jurors issue subpoenas for top state officials, including Raffensperger’s senior aides, Attorney General Chris Carr, House Speaker David Ralston and several other state legislators. They also request the appearance of the 16 “alternate” GOP electors.

June 29, 2022

Republican members of the General Assembly, including Lt. Gov. Geoff Duncan and former Sen. William Ligon, challenge their subpoenas in court. The group argues it’s immune from testifying due to legislative privilege. McBurney eventually rules that the lawmakers are required to testify but that there are certain categories of questions that prosecutors can’t ask because of constitutional privileges.

July 5, 2022

The jury signs off on summons for several Trump confidantes and former lawyers who live outside of Georgia. Among those who received the so-called certificates of material witness, which essentially function as subpoenas once approved by judges in their local jurisdictions, were Rudy Giuliani, John Eastman and U.S. Sen. Lindsey Graham.

July 6, 2022

Graham (R-S.C.) vows to fight his subpoena, calling the Fulton probe a “fishing expedition.” He argues the Constitution’s “Speech or Debate” clause shields him, as a member of Congress, from having to testify. Graham eventually files a motion to quash his subpoena in a Georgia federal court.

July 15, 2022

News breaks that two high-ranking Georgia Republicans who served as “alternate” presidential electors — GOP chairman David Shafer and state Sen. Burt Jones, who had weeks earlier won the Republican nomination for lieutenant governor — received letters informing them that they’re “targets” of the investigation and that they could be indicted. Days later, the DA’s office disclosed that all 16 GOP electors were sent target letters.

July 18, 2022

Georgia U.S. Rep. Jody Hice, R-Greensboro, becomes the second member of Congress to challenge a subpoena issued by the grand jury. A federal judge later rules that Hice had to testify but that there were certain subjects that prosecutors couldn’t ask him due to legislative privilege.

July 20, 2022

New York State Supreme Court Justice Thomas Farber orders Giuliani to appear before the Fulton special grand jury after the former New York City mayor fails to attend a previously-scheduled hearing to challenge his subpoena.

July 21, 2022

McBurney hears a legal challenge from Jones seeking to disqualify Willis and her office from investigating him. Jones argues that Willis has a conflict of interest because of a fundraiser she held for his Democratic opponent for lieutenant governor, Charlie Bailey. Four days later, McBurney sides with Jones, barring Willis and her office from questioning or investigating the legislator. His move allows the Prosecuting Attorney’s Council of Georgia, a-state agency that assists Georgia’s district attorneys, to appoint another set of prosecutors to determine whether to subpoena Jones or charge him with any crimes.

Aug. 15, 2022

Federal U.S. District Court Judge Leigh Martin May denies Graham’s bid to quash his subpoena, ruling that Willis “has shown extraordinary circumstances and a special need for Senator Graham’s testimony.” Graham’s lawyers quickly announce they’re appealing the ruling to the 11th Circuit Court of Appeals.

Aug. 17, 2022

Giuliani testifies before the special grand jury for roughly six hours, an appearance that draws dozens of reporters and television crews to downtown Atlanta. The blockbuster appearance came two days after one of Giuliani’s attorneys confirmed that their client was informed he’s a target of the investigation.

Aug. 17, 2022

Attorneys for Gov. Brian Kemp file a motion seeking to kill a subpoena for his testimony before the special grand jury. The summons was issued after plans for a voluntary interview with Fulton prosecutors were scuttled after an apparent communication breakdown with the DA’s office. About two weeks later, McBurney rules that Kemp must testify, but delays his testimony until after the November elections.

Aug. 25, 2022

The grand jury issues additional summons seeking testimony from a fresh batch of Trump allies, including former White House Chief of Staff Mark Meadows, Trump campaign attorney Sidney Powell and adviser Boris Epshteyn. It’s also soon revealed that they’re seeking testimony from libel attorney and election denier Lin Wood and evidence from Atlanta data services firm SullivanStrickler.