For those who have closely followed every twist and turn of the investigations of President Donald J. Trump, there were new developments during Michael D. Cohen’s congressional hearing on Wednesday in front of the House Oversight and Reform Committee.

But for many watching, the standout moments came in the fiery, and occasionally puerile, exchanges between Mr. Cohen, President Donald J. Trump’s longtime lawyer, and Republican committee members set on impugning his credibility.

[Follow the hearing live with commentary from our reporters.]

“Liar, Liar”

Paul Gosar, a Republican representative from Arizona, reflected the tone of many of the Republican members’ exchanges with a sign set up behind his chair, displayed from the beginning of the hearing. The sign showed a picture of Mr. Cohen superimposed on flames, emblazoned with the words “LIAR, LIAR, PANTS ON FIRE!”

Following Mr. Gosar’s questioning (in which he mocked Mr. Cohen’s apparent desire to be seen as a sex symbol), Mr. Cohen said that he was the one responsible for the congressman’s tactics.