Trump[,] Jr.

Andrew Boynton of The New Yorker writes about “The Correct Punctuation of Donald Trump, Jr.,’s Name” — by which he means The New Yorker’s punctuation of that name.

But it’s too simple to say that Trump, Jr., with a comma, is “the“ correct punctuation. It’s correct for The New Yorker, whose use of a comma to set off Jr. as parenthetical leads to the period-comma-apostrophe pileup of Jr.,’s.

So: comma, or no comma? Bryan Garner’s Garner’s Modern English Usage (2016) says that both choices are correct. “Journalistic style-books,” he observes, prefer commaless Jr., “probably because newspapers generally disfavor optional commas.” But Garner adds that “the commaless Jr. has logic on its side.” He cites E.B. White’s explanation of the switch to commaless Jr. in the third edition of The Elements of Style:

Although Junior, with its abbreviation Jr., has commonly been regarded as parenthetic, logic suggests that it is, in fact, restrictive and therefore not in need of a comma.

Garner’s conclusion:

Besides logic, the commaless form probably has the future on its side; for one thing, it makes possessives possible (John Jones Jr.’s book). The with-comma form has recent (not ancient) tradition on its side. Posterity will be eager to discover, no doubt, how this earth-shattering dilemma is resolved in the decades ahead. One consideration that militates in favor of the commaless form is that, in a sentence, one comma begets another: “John Jones, Jr. was elected” seems to be telling Jones that Jr. was elected. With a comma before Jr., another is needed after: “John Jones, Jr., was elected.”

A writer can of course make a possessive form with a comma, as The New Yorker has: Jr.,’s. I think though that a style choice that eliminates any possibilty of .,’ is the better choice.

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[In earlier editions of The Elements of Style, William Strunk Jr. was William Strunk, Jr. What form does Garner’s Modern English Usage use? No comma.]