As posted on Always Put a Comma Before “and” in a List, No Matter What Your Old Grammar Teacher Said
Do you go to the store for “cupcakes, vanilla, and chocolate” or “cupcakes, vanilla and chocolate”? There’s a long-running debate over whether it’s proper to include that last comma in a list. Well, forget proper. The comma makes things clearer, and a recent lawsuit proves that.
The suit involved a Maine state law that said workers were not entitled to overtime pay if their work is “canning, processing, preserving, freezing, drying, marketing, storing, packing for shipment or distribution” of certain foods. Truck drivers sued, saying that they deserve overtime because their job is distribution. They do not do “packing for shipment or distribution”. The court agreed: if the state wanted “distribution” to be its own item in the list, they should have used a damn comma.
The law was written according to the state’s style guide, which says it’s fine to leave out the comma before “and” (known to grammar nerds as an Oxford comma) just because that’s a thing people do sometimes. But the court is right: if you want to clearly identify the items in your list, consider your commas carefully.