In September, the committee included Mr. McCarthy on a list of hundreds of people whose records it instructed social media and telecommunications companies to preserve for possible use in the inquiry, which was reported earlier by CNN and confirmed by The New York Times. Mr. McCarthy’s spokesman, Mark Bednar, criticized the panel at the time as “politically motivated” and categorized its request as “an authoritarian, unconstitutional attempt to rifle through individuals’ call logs.”
In the days after the mob attack, Mr. McCarthy struck a different tone. He initially condemned the violence and said Mr. Trump “bears responsibility” for the violence.
“What we saw last week was not the American way,” Mr. McCarthy said on the floor of the House. “Neither is the continued rhetoric that Joe Biden is not the legitimate president.”
But Mr. McCarthy eventually changed his stance, re-embracing Mr. Trump — who remains popular among the Republican base — and visiting him at his Mar-a-Lago club in Palm Beach, Fla., near the end of January.
“Your public statements regarding Jan. 6 have changed markedly since you met with Trump,” Mr. Thompson wrote in his letter. “At that meeting, or at any other time, did President Trump or his representatives discuss or suggest what you should say publicly?”
In a recent interview, Representative Liz Cheney, Republican of Wyoming and the vice chairwoman of the committee, pointed to the Mar-a-Lago meeting as a turning point for Mr. McCarthy. He would later lead his party’s effort to oust her from her leadership post for continuing to call out Mr. Trump, his election lies and the complicity of many Republicans in spreading them. And after initially saying he would back a bipartisan inquiry into the Jan. 6 attack, he reversed course and argued vociferously against any investigation by Congress.
“Looking back, the moment that Leader McCarthy went to Mar-a-Lago near the end of January, it was pretty clear the path that he had chosen,” Ms. Cheney said. “It was one that was not faithful to the Constitution. I believe we have a duty to our oath of office that requires that you put that above politics.”