Fulton County Superior Court Judge Robert McBurney said Graham would be asked to arrive before a special-purpose grand jury probing the actions of former President Donald Trump and his allies on Aug. 2, "continuing through and until the conclusion" of the witness testimony on or before Aug. 13.
"The court finds that the Witness, based on the substance and timing of the telephone calls he personally made to Georgia Secretary of State Brad Raffensperger, is a necessary and material witness in this investigation," McBurney wrote in a court filing Monday reported by Fox 5 Atlanta. "The Witness's anticipated testimony is essential in that it is likely to reveal additional sources of information regarding the subject of this investigation."
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Graham's subpoena stressed that he had two known calls with Raffensperger after the 2020 election.
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"During the telephone calls, the witness questioned Secretary Raffensperger and his staff about reexamining certain absentee ballots cast in Georgia in order to explore the possibility of a more favorable outcome for former President Donald Trump," the subpoena reads.
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Lawyers for Graham slammed the subpoena earlier this month as "all politics" and an erosion of the balance of powers.
"As Chairman of the Senate Judiciary Committee, Senator Graham was well within his rights to discuss with state officials the processes and procedures around administering elections," his lawyers, Bart Daniel and Matt Austin, said in a statement.
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Graham's lawyers also stressed that "any information from an interview or deposition" in Fulton County would likely be shared with the House Jan. 6 committee.
Willis has been investigating whether Trump or his allies had any wrongdoings after the election by improperly seeking to overturn the election in the Peach State. The special grand jury was impaneled in May to aid in the inquiry and issue subpoenas.
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Trump has disavowed any wrongdoing and dismissed Willis's investigation as another politically motivated "witch hunt." Other people close to Trump, including his former personal lawyer Rudy Giuliani, have also been subpoenaed in the inquiry.
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Willis also left open the possibility of issuing a subpoena to Trump, commenting that "anything's possible" in an interview with NBC News.
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"We’ll just have to see where the investigation leads us," Willis said. "I think that people thought that we came into this as some kind of game. This is not a game at all. What I am doing is very serious. It’s very important work. And we’re going to do our due diligence and making sure that we look at all aspects of the case."
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