A conservative watchdog group is suing the Justice Department to find out if former FBI Director James Comey “coordinated” with special counsel Robert Mueller before Comey’s appearance before Congress.

Judicial Watch wants “all records of communications” between Comey and the Justice Department, which would include communications to Mueller, in the run-up to Comey’s appearance before the Senate Intelligence Committee in June. Congressional investigators wanted information on Comey’s firing by President Trump, as some lawmakers suspected the move was an attempt to impede a federal investigation into whether his campaign coordinated with the Russian government’s cyber attacks against the Democratic party in 2016.

The Justice Department missed a deadline to release the documents voluntarily under the Freedom of Information Act.

“It would be a scandal if Comey coordinated his Senate testimony with Mr. Mueller’s special counsel office,” Judicial Watch President Tom Fitton said Tuesday. “That we have had to sue in federal court speaks volumes.”