Oh noble CAAFlog readers. I have a question for you. Let’s say I want to refer to the joint opinion of Justices O’Connor, Kennedy, and Souter in Planned Parenthood v. Casey, 505 U.S. 833 (1992). Now let’s suppose I want to construct the sentence using the possessive case. Which is right:
(a) Justices O’Connor, Kennedy, and Souter’s joint opinion in Casey; or
(b) Justices O’Connor’s, Kennedy’s, and Souter’s joint opinion in Casey?
I had long used the latter construction, reasoning that it better alerts the reader that I am using the possessive case. (I would make an exception where more than one possessor is commonly understood as one entity — thus, I would write, for example, “Lewis and Clark’s expedition” rather than “Lewis’s and Clark’s expedition.”)
While I have traditionally used form b, I have noticed in my reading that almost everyone else seemed to use form a. And I couldn’t find the answer in any of the grammar books that I usually consult. I was almost ready to throw in the towel and submit to the apparent form a orthodoxy. So imagine my delight upon reading the new biography of Shakespeare by Bill Bryson (whose writing I adore) and discovering the following description of Edmond Malone: “He became a friend of James Boswell’s and Samuel Johnson’s . . . .” Bill Bryson, Shakespeare: The World as Stage 175 (2007).
So which is right? And, most importantly, does anyone have a citation to an authoritative grammar text’s answer to the question?