Fulton County District Attorney Fani Willis plans to fight a subpoena she received from a state Senate committee in court on Thursday, according to her office.

The Democrat recently received a summons from the Republican-led Senate Special Committee on Investigations and Fulton Superior Court Judge Shermela Williams has scheduled a hearing for Thursday afternoon, said Willis’ spokesman Jeff DiSantis.

The hearing is expected to allow the DA’s personal attorney, former Gov. Roy Barnes, to argue why the veteran prosecutor should not be held in contempt for refusing to obey a subpoena.

The fight has been months in the making.

Willis and Barnes, also a Democrat, have argued that the investigative panel acting alone does not have the legal authority to compel her testimony.

Bill Cowsert, the Athens Republican who leads the Senate committee, said he believes “the law is clear” that his panel has the legal authority to force Willis’ attendance.

“The legislative branch has the inherent power to investigate and to utilize subpoenas,” he said earlier this spring.

Barnes and Cowsert did not immediately respond to requests for comment on Wednesday.

It is unclear whether Willis, who is leading the high-profile election interference case into former President Donald Trump and 14 others, will attend Thursday’s hearing.

Cowsert’s committee was created earlier this year as nine defendants in the election case, including Trump, sought to disqualify Willis from the prosecution because of a romantic relationship she had with Nathan Wade, the private attorney she hired to oversee the case.

The committee’s GOP boosters designed it to investigate whether Willis had any conflicts of interest or misspent any public funds, including during vacations with Wade. While it lacks the power to prosecute, disbar or directly discipline Willis, it can recommend changes to the state budget or draft legislation setting stricter oversight guidelines for prosecutors.

Cowsert told The Atlanta Journal-Constitution last month that he is considering legislation that would regulate district attorneys’ conduct and the use of special grand juries and special prosecutors but that he also wanted to hear directly from Willis.

Willis has described the committee as highly partisan and accused GOP senators more broadly of targeting her because “they worry their hero is treated the same as everybody else,” referring to Trump.

Never been tested

The Legislature’s subpoena power has never been tested under Georgia law, according to legal experts previously interviewed by the AJC. They expect the fight will likely end up before the state Court of Appeals, the same body that is currently considering whether Willis should be removed from the election case.

Attorney Joseph Young, Barnes’ onetime legislative counsel, said the Legislature can issue subpoenas either through the House or Senate Ethics committees or the General Assembly acting as a whole — not just a single chamber working on its own.

David Cook, the secretary of the Georgia Senate, has pointed to several U.S. Supreme Court decisions “confirming the inherent constitutional power of a legislative body” such as the state Senate “to investigate and oversee the affairs of state.”

“This is well settled constitutional law,” he said, adding that state statutes also grant the Senate the power to conduct investigations, issue and enforce subpoenas.

A report issued by the General Assembly’s Office of Legislative Counsel in 2016 notes that the branch’s investigative powers may be exercised through its committees, including single-chamber special committees, if they are delegated such powers. The resolution passed by the Senate earlier this year that created the Willis investigative committee specified that the panel has subpoena power.

Pete Skandalakis, the head of the Prosecuting Attorneys’ Council of Georgia, previously noted the lack of case law on legislative subpoena power. But he said his organization believes the statute that gives the ethics committees the ability to issue subpoenas and punish contempt, combined with language in the state Constitution allowing the General Assembly to handle matters like contempt, “may provide the courts an avenue to allow legislative committees to issue subpoenas.”