In order to appear before the House select committee looking into the January 6, 2021 Capitol Hill uprising, Wisconsin House Speaker Robin Vos was served with a subpoena over the weekend. This spurred Vos to file an urgent lawsuit.

According to federal court records, Vos sought a federal judge in Wisconsin to quash the subpoena, which demanded that he give testimony on Monday at 10 a.m. ET, two days before the committee’s subsequent open meeting. According to a person familiar with Vos’ subpoena, Vos will not testify before the committee on Monday after his attorney met with the panel and the House received copies of his legal challenge.

The judge has not yet given a response.

Vos claims that the committee wishes to interrogate him on a conversation he had with former President Donald Trump in July following the state courts’ decision to prohibit the use of some absentee ballot dropboxes, during which Trump “asked Speaker Vos take future actions.”

In the waning days of his reelection campaign, “the Committee is demanding Speaker Vos attend for a deposition to answer questions extraneous to the Committee’s inquiry, with virtually no warning,” according to his lawsuit.

Vos is contending that the subpoena “seeks to impinge on Speaker Vos’ legislative immunity” from litigation and is contesting the legitimacy of the House committee in court.

Other House witnesses have filed similar claims, but none of them have been successful or had their cases determined yet.