Liz Cheney, the former Republican lawmaker who has positioned herself as a political opponent to Donald Trump, summed up Sen. J.D. Vance's position on presidents obeying Supreme Court rulings in two words.

“That’s tyranny,” Cheney wrote Monday on Twitter.

Cheney was addressing Vance after he went on ABC News Sunday and told George Stephanopoulos that a sitting president could defy rulings from the Supreme Court.

“If the Supreme Court said that the president of the United States can’t fire a general,” Vance said, “that would be an illegitimate ruling and the president has to have Article 2 prerogative under the Constitution to actually run the military as he sees fit.”

Vance also asserted he would not have certified President Joe Biden’s election had he been vice president on Jan. 6, 2021, when rioters stormed the U.S. Capitol in an attempt to prevent Mike Pence from doing just that.

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“If I had been Vice President,” Vance said, “I would have told the states…we needed to have multiple slates of electors.”

Those multiple elector slates are at the heart of two criminal court cases Trump faces in Georgia and Washington D.C. where the former president faces election interference charges, as Cheney pointed out Monday.

“Vance also admitted he would have done what VP Pence refused to do on January 6th—help Trump illegally seize power,” Cheney wrote on X. “Neither Trump nor Vance is fit to serve.”

Vance’s controversial Supreme Court statement spurred Stephanopoulos to cut the interview short, snapping at the Republican lawmaker, “You’ve made it very clear: You believe the president can defy the Supreme Court.”

Vance is one of several Republicans vying to be Trump's running mate on the 2024 presidential ballot.