If you want to provoke a fight among English grammarians, the quickest way to do so is to mention the Oxford comma. It doesn’t matter if you use it or not, its existence inflames passions on both the pro and con side. What is this piece of grammar that causes such excitement?

The Oxford comma functions as a serial comma, which means it separates the items in a series, especially when there are three or more items involved. According to one of my favorite grammar books Commas Are Our Friends by Joe Devine, the comma takes the place of constantly using the word “and.” It tells you how many items are included in the series. The example this book gives is: James, George, Roy, Martin and Fred all went to Bill’s house last night for dinner. Six men ate according to this sentence. Yet, by rearranging the commas, only four men sat down for dinner: James George, Roy Martin and Fred all went to Bill’s house last night for dinner. Neither of these two example sentences uses the Oxford comma (placing a comma between “Martin” and the “and”) because this book doesn’t favor its use. So for a long time, neither did I.

Those against placing a comma at the end of a series argue that the word “and” takes the place of the last comma. This can be a tricky point. What is considered an item in a series? My book Short Cuts to Effective English by Harry Shefter points out that bacon and eggs can either be considered one item or two. Look at these sentences:

This morning I had coffee, bacon and eggs.
This morning I bought coffee, bacon, and eggs.

Should the bacon and eggs be regarded as one item or two? As you can see from each sentence, it depends upon the context. In the breakfast example, they are one dish; in the grocery example, they are two different purchases. Another example of a single unit would be fish and chips. This book is in favor of placing a comma before the final “and” in a series (using the Oxford comma), unless that word is for a single item made up of two parts.

The Short Cuts book favors using the Oxford comma and gives an example of an inheritance. A will states that “$15,000 is to be shared by Lavinia, Karl and Thomas.” The resulting lawsuit has Lavinia claiming $7,500, because Karl and Thomas should be considered a group, like bacon and eggs. The court sided with her. So instead of the $15,000 being equally divided three ways, she got half and each of the men received $3,750.

Recently there was an actual court case that revolved around the use or actually the lack of an Oxford comma. The drivers sued their company for overtime pay. This was the sentence at the center of the case: The canning, processing, preserving, freezing, drying, marketing, storing, packing for shipment or distribution of: and the rest of the document listed the products involved. Notice there is no comma between “packing for shipment” and “or distribution of,” which means packing and distributing are not separate things. They are a group like bacon and eggs. The drivers distribute the products, but they don’t pack. Since they don’t perform both items in the group, they claimed they were owed overtime pay for the distribution. The court agreed with them. Not using an Oxford comma was costly. (The footnote to the article points out the Associated Press Stylebook adhered to by CNN doesn’t use the Oxford comma either.)

I didn’t use the Oxford comma either, until the presentation by Angela James to my RWA chapter in April. One of her slides read as follows: “Can one of you monitor our social media while I’m gone?” The answer was: “Amy, Larissa and I will take care of it.” The message was Amy didn’t have to worry because Larissa and you would handle it, which wasn’t true. Actually, the message should read: “Amy, Larissa, and I will take care it,” meaning all three of us will handle it while you enjoy your vacation.

The classic Oxford comma example as pointed out by my Second Son (a strong proponent of the comma) is: We invited the strippers, JFK, and Stalin. No comma after JFK means the strippers are named JFK and Stalin. Another sentence fragment that appeared in a book dedication and needed the Oxford comma was: With gratitude to my parents, Mother Teresa and the pope.

So despite what the AP Style book states, I have converted to using the Oxford comma in my future sentences listing a series. Isn’t grammar fun?