That versus which.
With some trepidation, this week the Scribe wades into the “that” versus “which” debate. The trepidation results from the competing views about the best way to describe the proper usage of these relative pronouns. Since there’s no unanimity, we’ll try it in a few different ways and hope that one makes sense to you.
Here’s one way to view it: “that” introduces a restrictive clause (one that can’t be left out without changing the meaning of the sentence)—while “which” introduces a nonrestrictive clause (one set off by commas and whose omission would not change the sentence’s meaning). E.g.,
Please buy the tickets that are needed for our train trip.
Popsicles, which are served frozen, are a popular summer treat.
The Oregon Supreme Court, which is the state’s highest court, only hears cases of broad significance.
Circuses that have tigers are exciting.
Here’s another way to look at it: “that” is used to narrow a category or identify a particular item being discussed. In the examples above, “that” was used when we were discussing only the tickets that are needed for our train trip (rather than all tickets) and only those circuses that have tigers (rather than all circuses). But “which” is used not to narrow a class or identify a particular item, but to add something about an item already identified. E.g.,
The Supreme Court’s decisions, which are published in the Oregon Reports, constitute the common law of Oregon.
The Ninth Circuit’s decisions that are published in the Federal Reporter are the cases the court deems to have precedential value.
The first sentence was discussing all of the Supreme Court’s decisions, without limitation, so “which” was used to introduce the nonrestrictive clause. But the second sentence pertained to only a subset of the Ninth Circuit’s decisions—those that were published. So “that” was used to introduce the restrictive clause (restrictive because it narrowed the category of cases from all decisions down to only those decisions the court published).
To add to the confusion, some authorities suggest a third, “comma test,” approach: if the phrase needs to be set off by commas, then it probably requires “which” and not “that,” e.g.,
The crowd that watched Ted Williams’s last game was thrilled that he hit a home run in his last at-bat.
Fenway Park, which is located in Boston, is home to the Boston Red Sox.
But if the phrase doesn’t need to be set off by commas, then it probably requires “that” and not “which,” e.g.,
The decision that the judge made regarding the summary judgment motion was contrary to the legal standard.
See? This is a perplexing tangle. Especially since sometimes the same sentence can correctly use either “that” or “which,” depending on meaning, e.g.,
The statement that she gave to the police was clearly a lie. (Correct if she gave more than one statement and it is necessary for clarity to identify the one to the police.)
The statement, which she gave to the police, was clearly a lie. (Correct if she gave only one statement and the adjectival clause serves only to give extra information.)
So … what is the Scribe’s preference? The Scribe prefers the first approach, which is to use “that” with restrictive clauses and “which” with nonrestrictive clauses (as it was used in this sentence). It is the simplest rule, and simple is good.
That is all for now …