Former White House chief of staff Mark Meadows has been called to testify by a Georgia district attorney after an escalation in the investigation of former President Donald Trump and his associates.

Fulton County District Attorney Fani Willis filed the petition to have Meadows testify along with Sidney Powell, James “Phil” Waldron, and former Trump campaign adviser Boris Epshteyn. They are all to testify in front of a special grand jury in Atlanta next month.

As they aren’t Georgia inhabitants, Willis has to involve judges from the states they reside to get them to appear for trial. The investigation is looking to see whether state laws were broken by Trump and his allies when they attempted to overturn the 2020 election resets in Georgia. The trial is the continuation of an 18-month investigation and will take place ahead of the November midterm election.

The petitions were signed off by Fulton County Superior Court Judge Robert McBurney, who is in charge of overseeing the special grand jury. According to the request, all of the witnesses’ testimonies are “necessary”.

Willis also wrote that they all had exclusive knowledge and communication with Trump and his campaign, so they would have information on the coordinated efforts made to alter the results of the 2020 November election.

A similar petition was also signed last month by the district attorney in which 7 others of Trump’s associates were called in. these included former New York City Mayor and Trump lawyer Rudy Giuliani and U.S. Sen. Lindsey Graham, R-S.C.

Giuliani testified in front of the jury last week, while Graham is still fighting his subpoena.  Republican Georgia Gov. Brian Kemp also appeared in court to fight against testifying in front of the grand jury.