Sen. Al Franken (D-Minn.) has apologized to Minority Leader Mitch McConnell (Ky.) after the freshman lawmaker made rude faces at the chamber’s top Republican while he was making his closing statement on the nomination of Elena Kagan to the Supreme Court.

Franken was the presiding officer during McConnell’s closing statement. As the GOP leader criticized Kagan, Franken repeatedly shook his head, chortled and made disapproving faces, according to Republican aides.

The display caught McConnell’s attention, and he rebuked his young colleague after concluding his remarks. “He said, ‘This isn’t “Saturday Night Live” anymore, Al,'” said a GOP aide familiar with the situation.

Franken later sought out McConnell to apologize.

“The Leader thought I was disrespectful while he was giving his speech on General Kagan,” Franken said in a statement. “He is entitled to give his speech with the presiding officer just listening respectfully. I went directly to his office after I was done presiding to apologize in person. He wasn’t there, so I’ve sent him a handwritten note.”

Senators typically take great pains to maintain an extreme level of courtesy in the Senate chamber. Even in the most heated of speeches, Members refer to each other as “my dear colleague” or “my good friend.”

But there have been some significant exceptions. For instance, former Vice President Dick Cheney famously told Sen. Patrick Leahy (D-Vt.) to “go f— yourself” in 2004, when he was presiding over the Senate.

Sen. Robert Byrd (D-W.Va.), who died this year, and Sen. Jim Bunning (R-Ky.) had a heated exchange on the floor in 2008, when Byrd questioned Bunning’s credentials as a Senator and mockingly referred to him as “a great baseball man.” Bunning is a former major league pitcher and is in the National Baseball Hall of Fame.

And in 1856, Sen. Charles Sumner (D-Mass.) was savagely caned by Rep. Preston Brooks (D-S.C.) after Sumner gave a floor speech attacking one of Brooks’ home state Senators.