Lindsey Graham has challenged a subpoena to testify before a special grand jury that's investigating whether then- President Donald Trump and others broke any laws when they tried to overturn Joe Biden's win in Georgia

Graham's lawyers said in a court filing that he was subpoenaed to testify before the grand jury in August. The special grand jury is being overseen by the Fulton County Superior Court judge.

Graham's lawyers say that he fought the subpoena last week. He denied that he was involved in the election.

Graham made at least two telephone calls to Georgia Secretary of State Brad Raffensperger and members of his staff in the weeks after Trump's loss to Biden, according to a court filing.

Graham's lawyers said in a court filing that he was engaged in quintessentially legislative fact finding when he made those calls.

According to Graham's lawyers, the U.S. Constitution provides absolute protection against inquiry into the senator's legislative acts. Sovereign immunity prevents a local prosecutor from trying to get a U.S. senator to testify. They say that the "extraordinary circumstances" needed to order a high-ranking federal official to testify have been missed.

His lawyers are asking for an expedited consideration of his motion to quash.

Jody Hice filed a challenge in federal court after he received a subpoena to testify. A federal judge last week refused to quash his subpoena after hearing arguments from both sides.

Fulton County Superior Court was told by the U.S. District Judge that there are some questions that Hice may have to answer. She said that if there are disagreements over whether Hice is protected from answering questions, he can bring them back to her.

The scope of the investigation includes a phone call between Trump and Raffensperger in January of 2021.

During that call, Trump said that he wanted to find more votes.

Trump has denied any wrongdoing and has called his call perfect.