WASHINGTON — The Supreme Court on Monday refused to take an appeal by former lawyer related to emails of his turned over to the House committee investigating the , Capitol riot.

Justice was not involved in considering or deciding Eastman's request that the Supreme Court toss lower court rulings related to the emails, the court said in declining to hear the case.

Thomas' recusal, which was not explained, is the first time he has removed himself from a case involving the Jan. 6 insurrection by a mob of supporters of former President .

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Eastman is a former law clerk for Thomas, and some of the emails given to the committee by his former employer Chapman University were between Eastman and Thomas' wife, Ginni.

Thomas is under heightened scrutiny over his to a conservative billionaire, , which Thomas failed to disclose for years.

His wife played a role in the to keep Trump in power after his loss to President in the 2020 presidential election.

A Supreme Court spokesperson did not respond to CNBC's inquiry Monday about what prompted Thomas' recusal.

"We're disappointed, of course, that the Court did not accept our request to correct this clear violation of its Munsingwear doctrine," Anthony Caso, a partner at Constitutional Counsel Group who represents Eastman, told CNBC. That doctrine requires the vacating of lower court decisions that have become moot.