I’ve been told that in legal documents in the US, the comma is necessary. If, for example, you leave a will for $6 million, to be divided equally between four people: Paul, Jan, Joan, and Bill will each get $1.5 million. But Paul, Jan, Joan and Bill wil get $2/$2/$1/$1 million.
It was heresay information, though, and I’m prepared to be corrected.
Personally, I vote for using the comma.
I think you should be consistent. That’s the whole point of stylebooks. If you start flip-flopping on how you punctuate certain things, you run the risk of confusing the reader. Inconsistent use of punctuation drives me batty–like reading a Middle English text before orthography was standardized.
What happens when you mix comma style rules with “major city so drop the state” style rules? This (from CBS MarketWatch):
The AP had it very ugly when it first came out, using all commas in this sentence, but they fixed it to use semicolons, thus thwarting my plan to mock them:
As someone else noted, both styles of punctuation are acceptable. The one you found is the most commonly-known difference between the Associated Press Style Guide and the University of Chicago Style Guide (aka The Chicago Manual of Style).
Since I’m a tech writer, I follow Chicago. Just the site of its bright orange cover brings a tear to my eye :rolleyes: If I was a journalist, and followed the Chicago style, an editor would correct me. IMHO, this is nit-picking, but its what makes the writing world go 'round.
I’m a sub-editor, and I say no to the Oxford comma – unless leaving it out would cause ambiguity. (Ha, what a cop-out!) Where the listed items include commas, I’d use semicolons.
So:
I went to the grocer’s and bought apples, bananas, guavas and pears.
We couldn’t be bothered to cook so we ordered pizza, Chinese, and fish and chips. [Although I would maybe opt to change the order to make it clearer]
Britney’s tour took in Bandar Seri Begawan, Brunei; Ouagadougou, Burkina Faso; and Tallahassee, Florida.