State Sen. Doug Mastriano, the Republican nominee for Pennsylvania governor, has submitted documents to the congressional committee investigating the deadly Jan. 6, 2021, Capitol attack and has agreed to be interviewed, his lawyer said Thursday.

Mastriano submitted the documents on Tuesday, Politico first reported, including receipts for $3,354 for buses he rented to bring supporters to the rally in Washington that devolved into the Capitol insurrection. Mastriano, a leader of the election denial movement in Pennsylvania, also submitted a manifest of passengers, showing he sold more than 130 tickets for the buses.

Mastriano also submitted a tranche of documents he had tweeted after the 2020 presidential election, calling on his colleagues in the state legislature to stop the certification of the results based on false and debunked fraud claims.

Timothy Parlatore, Mastriano’s lawyer, told The Inquirer Mastriano would cooperate with the committee but struck a combative tone about its powers and motivations to investigate the attack on the Capitol.

Parlatore also said Mastriano was interviewed by FBI agents last year about Jan. 6.

“He cooperated fully and no further action was required, as he clearly was not involved in any criminal activity,” Parlatore said.

Parlatore also said the committee, which issued a subpoena to Mastriano in February, “doesn’t have the power to compel” Mastriano’s testimony. Mastriano, he said, has agreed to a private “voluntary interview,” which has not been scheduled.

“If they call him for a public hearing, that they have the power to do,” Parlatore said. “I very much doubt they would want to do that.”

Mastriano won the primary last month by a wide margin despite a late effort by some establishment Republicans to stop him. He’s facing state Attorney General Josh Shapiro, the Democratic nominee, in the general election.

» READ MORE: Mastriano embodies a Christian nationalist movement as he runs for governor: ‘We have the power of God’

The February subpoena demanded information about Mastriano’s “knowledge and participation in an attempt to create an alternate slate of electors” after the election, his communications with former President Donald Trump about “your postelection activities,” and his participation in the events of Jan. 6

Mastriano called for a full audit of the vote in Pennsylvania 10 days after the 2020 election, and for delaying certification until that was completed.

He also hosted a state Senate hearing in Gettysburg that aired false fraud claims, with Trump calling in and testimony from Trump attorney Rudy Giuliani. Later that day, he attended a meeting at the White House on post-election strategy but quickly left after testing positive for COVID-19.

And he circulated memos to colleagues calling for an alternate set of electors, which became legislation that was not acted on.

Parlatore, who has represented two other clients subpoenaed by the committee, claimed it conducts private interviews and only releases transcripts if “it’s something that is politically useful.”

“This is not a real committee doing real investigation,” he said. “This is just a partisan pre-election stunt. Really, they’re not interested in getting any information from Mastriano. This is a fishing expedition where they were hoping he would refuse so they could imply he has something to hide.”

A spokesperson for U.S. Rep. Bennie Thompson (D., Miss.), who chairs the committee, did not immediately comment Thursday.

Mastriano, asked about the subpoena during a televised Republican primary debate in April, said he had “no legal issue” from his participation in the Jan. 6 rally.

“I was there to hear my president speak and then I was invited to speak in two locations, exercising my constitutional rights,” Mastriano said in the debate. “And shame on the media and the Democrats for painting anyone down there as a villain.”

Trump endorsed Mastriano for governor three days before the May primary, saying “no one in Pennsylvania who has done more, or fought harder, for election integrity.”