NARRATOR: Did you know that a punctuation mark can cost more than a Ferrari? A missing comma in a case about overtime payments cost the defendant $5 million. This $5 million comma isn't just any comma. It's the notorious Oxford comma. 

- Lawyers should always use the Oxford comma. 

NARRATOR: Amy Sloan is a law professor and co-author of the book Plain English for Lawyers, currently in its sixth edition. She's here to help explain why when it comes to legal writing, the Oxford comma isn't quite so controversial. 

- So the Oxford comma is also sometimes called the serial comma, and we use it when we have a series of items in a sentence. 

NARRATOR: That comma that comes before the "and," that's the Oxford comma. 

- Some people might say that having a conjunction between items in a list is sufficient to make the writing clear. Sometimes that's true. If we think about the Declaration of Independence, we have life, liberty and the pursuit of happiness with no Oxford comma. But we all know what that means. But in other cases, omitting the Oxford comma can create ambiguity. 

NARRATOR: Take a case from 2008, when a cat owner from New York was charged with animal abuse for not taking his sick cat to the vet. 

- The New York animal cruelty statute provided that an animal owner must provide necessary sustenance comma food or drink. The defendant argued that the phrase "food or drink" described what necessary sustenance was, and because he provided food or drink to his animal, he could not be guilty of animal cruelty. The plaintiff, of course, felt differently and said that each one of those items was a separate item in a list-- necessary sustenance, food, or drink, three separate items. Ultimately, the court sided with the defendant on that particular issue and said that the phrase "food or drink" describe what necessary sustenance was, although the defendant was still found guilty on other grounds. 

NARRATOR: In other cases, the lack of the Oxford comma creates ambiguity for a different reason. 

- It doesn't seem to make sense. 

NARRATOR: Such was the case of the $5 million comma. A dairy company in Maine was forced to pay that princely sum in missed overtime funds for wrongly interpreting a state law missing, you guessed it, an Oxford comma. 

- Questions about the use of the Oxford comma have even made their way all the way to the US Supreme Court. 

NARRATOR: In 1989, in the United States versus Ron Pair Enterprises, the court had to interpret the bankruptcy statute. 

- The court based its ruling, in part, on the way the comma was used within the statute. 

NARRATOR: And the problem goes beyond the courts. 

- Unclear writing in contracts and other instruments may not always lead to court cases, but they lead to controversy, confusion, and unhappiness among people who thought they understood what they were getting into in the contract. 

NARRATOR: So if the Oxford comma can save so many headaches, why not just use it? 

- In fiction and in other types of writing, an author may not use an Oxford comma because it suits their purpose. In law, however, it's important always to use it. If something ends up in litigation, the judges have no way to go back and ask people what did they mean when they wrote something. They have to go with what's on the page. And the Oxford comma is one of the tools available to make sure the reader understands how a list of items is intended to be interpreted. 

NARRATOR: So next time you wonder if one small punctuation mark can really make that much of a difference in law, just think, would you rather buy a car or a comma? 

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