A rare special grand jury is being convened in Georgia to tackle what promises to be one of the most challenging tasks in the state’s history: investigating a former president for trying to interfere in an election.

On Monday, the Fulton County District Attorney’s Office began narrowing down its pool of potential members for a special grand jury that will be tasked with aiding the investigation of former President Donald Trump. Once finalized, the special grand jury will be empowered to hear evidence from prosecutors and issue subpoenas to further the investigation into the ex-president.

In essence, a special grand jury is assembled through similar procedures as a typical grand jury. Where it differs is that a special grand jury is focused on a single issue and produces a report on its findings. It would then be passed to the district attorney, who then decides whether to seek an indictment from a regular grand jury.

At the center of the investigation is an infamous phone call Trump made on Jan. 2 to Georgia’s Secretary of State Brad Raffensperger. During a nearly hour-long conversation, Trump pressed Raffensperger to find him 11,780 votes that would allow him to claim victory in Georgia after the state was called for now-President Joe Biden, the first time the state went for a Democrat since 1992. Raffensperger refused and refuted Trump's claims of voter fraud.

Fulton County, which includes the city of Atlanta, opened the investigation on Feb. 10 after District Attorney Fani Willis received a request from a member of the Georgia State Election Board. Compared to parallel investigations into Trump in New York or in Congress, Willis has maintained a relatively low profile as her office pressed forward.

Once a grand jury is fully assembled, it will provide an avenue for compelling testimony from witnesses in the case. In particular, it would allow prosecutors to seek testimony from Raffensperger, who Willis previously said indicated he would only speak to her office if subpoenaed.

The case has naturally carried without a heavy amount of political sensitivity. Trump has denied any wrongdoing and has lashed out at Willis’ office, prompting her to seek protection from the FBI in January after a rally rant by Trump against her investigation.

Security has been increased around Fulton County as selection for the special grand jury continues. A task force of federal, state and local law enforcement has been assembled to ensure the security of the event, local media reported last week.