The select committee investigating the Jan. 6 Capitol riot is threatening to refer contempt of Congress charges to individuals who do not comply with its subpoenas.

“We will not allow any witnesses to defy a lawful subpoena or attempt to run out the clock, and we will swiftly consider advancing a criminal contempt of Congress referral,” Committee Chairman Bennie Thompson and Vice Chair Liz Cheney said in a joint statement released Friday. The committee announced on Sept. 23 that it issued subpoenas to four senior aides to former President Donald Trump: former chief strategist Steve Bannon, former White House Chief of Staff Mark Meadows, former Defense Department Chief of Staff Kash Patel and former White House Deputy Chief of Staff for Communications Dan Scavino.

NEW: ⁦@January6thCmte⁩ confirms our reporting that Steve Bannon has informed him of his plans to fight subpoena.
However committee says Mark Meadows and Kash Patel are “engaging” with the group.
We also reported Meadows had responded.
No mention of Dan Scavino. pic.twitter.com/x43RvsrPvv

— Ryan Nobles (@ryanobles) October 8, 2021

Trump has argued that executive privilege protects his top advisors from testifying in front of the committee, and a lawyer for Bannon said Thursday that Bannon would wait for federal courts to decide whether or not he is required to testify. (RELATED: Jan. 6 Committee Issues First Subpoenas To Four Trump Aides, Allies)

Bannon did not immediately respond to the Daily Caller’s request for comment.

The Biden administration will not attempt to assert executive privilege against the subpoenas due to the “unique and extraordinary circumstances” of the committee’s work, White House Counsel Dana Remus wrote in a letter to the National Archives.

Meadows and Patel are “engaging” with the committee, Thompson and Cheney said in their statement, while calling Bannon’s assertion of executive privilege “vague.” They did not mention Scavino, who has not yet been physically served with his subpoena, according to CNN.

“I can confirm that I have responded to the subpoena in a timely manner. Beyond that, I will not comment on my confidential dealings with the Committee. But I can assure you that I will continue to tell the truth and remain focused on Fight With Kash to help any American who has been censored and misrepresented online,” Patel told the Daily Caller in a statement.

Meadows did not immediately respond to the Daily Caller’s request for comment.

Patel and Bannon are expected to testify at depositions on Oct. 14, and Meadows and Scavino are expected to testify on Oct. 15.

Congress has three ways of enforcing subpoenas and holding individuals in contempt for violating them, according to the Congressional Research Service. Following a full chamber vote, the House or Senate Sergeant-at-Arms can detain a subpoenaed witness until he or she testifies. The Department of Justice may also enforce criminal contempt of Congress charges against individuals, and Congress can independently ask a federal court to enforce the subpoena.

The select committee has also issued subpoenas to 11 individuals who helped organize the “Stop the Steal” rally that immediately preceded the riot, as well as document requests to social media companies such as Facebook, Twitter, YouTube and Parler. The committee is also expected to request that telecommunications companies preserve the phone records of 11 House Republicans who it believes played a role in the rally.