AILSA CHANG, HOST:
As the U.S. Senate solemnly considers the fate of a president, Twitter has been somewhat less solemn, considering another question. Can you drink milk on the Senate floor?
ARI SHAPIRO, HOST:
As best we can tell, this debate started with a tweet by reporter Matt Laslo. He said Senator Rick Scott told him that the rules only allow senators to drink water and milk on the floor. To figure out why, we called a Senate historian emeritus.
DON RITCHIE: I tell people emeritus means no tie. I stopped wearing ties. But, actually, what it means is I worked for the Senate for 40 years. And when I retired, the Senate passed a resolution making me historian emeritus.
CHANG: That would be Don Ritchie. The rules about beverages, he says, can be traced back to the idea of decorum, a particular focus of Thomas Jefferson, who presided over the Senate while vice president.
RITCHIE: And he was pretty bored as just the presiding officer, and so he used his time to compile the first rules manual. And part of what he did was to suggest that you need to maintain decorum in the chamber. You need to cool things down. You need to get away from heated rhetoric.
SHAPIRO: And so senators are not allowed to criticize one another's states or their motives.
CHANG: And you can't read a newspaper while someone is speaking.
SHAPIRO: And you can't eat or drink in the Senate chamber.
CHANG: But senators are human beings with, you know, bodily needs.
RITCHIE: Senators spend a lot of time talking, and that means that they, sometimes, get very dry mouth.
SHAPIRO: Water, as we've already noted, is, of course, allowed. But then there's the filibuster.
CHANG: When senators talk for hours and hours and hours on end, a glass of water just does not cut it. And so, Don Ritchie says, the Senate made exceptions.
RITCHIE: We have accounts of senators conducting filibusters and ordering milk. I think Senator La Follette ordered a milkshake.
SHAPIRO: We'll note that the Senate Historical Office records that it was actually eggnog possibly spoiled by the Washington heat. But anyway, that's a different story.
CHANG: Ugh (ph). This, though, is where milk re-enters the picture. There is a note right there in "Riddick's Senate Procedure," a compendium of guidelines written by a former Senate parliamentarian.
RITCHIE: Which has all the precedents of the Senate - the Senate has actually very few rules but thousands of precedents. And the precedents outrule (ph) the rules.
SHAPIRO: And this precedent clearly states Senate rules do not prohibit a senator from sipping milk during his speech. Follow the footnote on that entry to the January 24, 1966 congressional record, and you will find Senator Everett Dirksen of Illinois in the middle of a long speech about the Taft-Hartley Act, asking the presiding officer this.
CHANG: Is it in violation of the Senate rules if the senator from Illinois asks one of the page boys to go to the restaurant and bring him a glass of milk?
SHAPIRO: The presiding officer tells him it is not, and the milk exception to the water rule was born. But Historian Emeritus Don Ritchie says it's just that - an exception.
RITCHIE: On a regular basis, you won't see people drinking milk and orange juice. At most, it's water.
CHANG: (Laughter) But not this afternoon - an eagle-eyed CBS News reporter spotted Arkansas Senator Tom Cotton with - you guessed it - a glass of milk. And he was not the only one.
SHAPIRO: About 20 minutes later, North Carolina Senator Richard Burr got his own glass of milk.
CHANG: Thank goodness for exceptions and precedent. Transcript provided by NPR, Copyright NPR.
