A reader named Jerry wrote to ask about “that” and “who.” Like a lot of people, Jerry had been taught that “that” is for things and “who” is for people, yet his reading materials didn't seem to agree.

“I am beginning to think I am wrong in the use of ‘who' and ‘that.' I see now in all newspapers quite regularly the term ‘people that' instead of ‘people who.' Is the word ‘that' now an acceptable replacement when talking about people or persons? It just doesn't sound right to me.”

Jerry isn't alone, as I would soon find out. In this column a few weeks ago, I offered readers a little catch-the-error test. It was loaded with tricky editing issues, including the phrase, “the two dozen Norfolk officers that responded.” In the next paragraph, I revealed that the real error was “Norfolk” — the sentence had created a scenario in which Virginia police were outside their jurisdiction.

But several readers wrote to tell me they caught a mistake I had not: the word “that.” It was used in error, they told me, in a phrase that should have been “the two dozen Norfolk officers who responded.”

The words “who” and “that” are called relative pronouns, a label they share with “which” and “whom.” A relative pronoun heads up something called a relative clause, whose job is to “post-modify” a noun. That just means it comes after a noun and works like an adjective to describe it.

In “the car that gets good mileage,” the relative clause “that gets good mileage” is modifying the noun “car.” In “the woman who got the job,” the relative clause “who got the job” is modifying the noun “woman.”

So “who” and “that” are part of the same word class and do the same basic job. But can “that” pinch-hit for “who” when the noun you're modifying happens to be a person?

Actually, not on my watch. When I'm writing, I always opt for “who” instead of “that” to describe people. As an editor, I follow the same guideline: When I'm editing an article in which the writer uses “that” for people, I almost always change it to “who” or “whom.” Yet my use of “the Norfolk officers that responded” wasn't an error.

It was a red herring — one of many in my deliberately tricky test.

I used “that” to refer to the officers precisely because a lot of people think “that” for people is wrong. It's not.

“‘That' refers to persons or things,” according to “Merriam-Webster's Dictionary of English Usage.”

“Down through the centuries, ‘that' has often been used with a human antecedent,” reports “Fowler's Modern English Usage,” which cites14th-century English poet Geoffrey Chaucer as being among the proponents of this usage.

“Webster's New World College Dictionary” defines “that” as, among other things, a synonym for “who.”

So there's nothing grammatically wrong with using “that” to refer to people. Yet a lot of people, present company included, believe “who” for people is better.

Writing teachers have long pointed out that because “who” is more specific to people, it's usually the better choice when referring to them. Why? Two reasons. It's more “human,” if you will, which can make writing more vivid. Also, as a rule, specific words are better at preventing reader confusion than broader, more generic alternatives.

So the idea that you should avoid “that” when referring to people is good advice. Just don't mistake it for a grammar rule.

JUNE CASAGRANDE is the author of “It Was the Best of Sentences, It Was the Worst of Sentences.” She can be reached at JuneTCN@aol.com.