Sen. Lindsey Graham (R-S.C.) is asking a federal court to quash a grand jury subpoena for his testimony in the Fulton County district attorney’s investigation into former President Trump’s efforts to undermine Georgia’s election results.

Graham intends to ask a federal judge to quash the subpoena on the grounds that he cannot be compelled to testify because his conversations with state officials were part of his official conduct as a legislator, according to copies of the filings provided to The Hill by Graham’s lawyers.

“Senator Graham’s contact with Georgia officials referenced in the Certificate falls within the ‘legislative sphere’ because it was to gather information relevant to his oversight responsibilities as Chairman of the Senate Judiciary Committee and given his obligations under the Electoral Count Act of 1887,” the filing reads.