Fact-checking is much in the news these days — or perhaps it’s the absence of it that’s much in the news.

It used to be, and may still be, that top-quality magazines had fact-checkers whose job was to go through every story accepted for publication and check all the facts. They weren’t responsible for the quality of the prose — just the facts.

Editing — specifically copyediting, which includes excruciating attention to detail — and fact-checking are two distinct tasks, but inevitably they overlap. Imprecise writing can lead to readerly misunderstanding, and those misunderstandings may have to do with facts. A trade publisher I’ve been working for regularly for many years directs copyeditors to check dates, the spelling of names, and anything that can be easily verified as long as it doesn’t add to billable time.

Before the World Wide Web, freelance copyeditors were limited to biographical dictionaries, atlases, specialized…