From elementary-school days, people learn—and should continue learning—how to write forceful and grammatically correct sentences. If you have this skill, you have a good start on writing well. But there’s much more to it. You must cultivate the skill of combining sentences into logically coherent paragraphs. By way of analogy, paragraphs are to sentences what sentences are to words.
There are three major reasons for paragraphing.
First, paragraphs make the page more inviting. On glancing at your pages, readers should get the feeling that your work will be easy to read. You’ll therefore want to avoid a series of long, forbidding paragraphs. A profusion of bulky paragraphs suggests either indiscriminate lumping or unnecessary padding. Think how often you’ve been repelled from a book by whole solid pages without paragraph breaks; and think, by contrast, how often you’ve yielded to the attraction of an open, easy-looking page.
Second, with a paragraph you signal your reader that you’re embarking on a new idea. There’s an implicit understanding that you group sentences into a paragraph to develop a clear point. It’s a matter of structural unity. With effective paragraphing, you subliminally reinforce the idea that you have a well-organized mind—and your work will be worth the reader’s time. If you struggle with paragraph unity, check your first sentence carefully to see what it says. Then see whether your next sentence takes up some prominent aspect of it and develops that idea.
Third, a new paragraph highlights the statement made at its outset, usually the topic sentence. The technique of highlighting points by paragraphing makes it easy for readers to follow along. A new paragraph is a visual technique of amplifying what you’re saying there.
In short, everything about effective paragraphing is conducive to ease in reading. Once you announce the topic of a paragraph, you’ll do one of five things: (1) tell a story; (2) draw a picture; (3) provide proof; (4) assess advantages or disadvantages; and (5) analyze by stressing individual components.
Whatever the approach, the ideas should unfold sensibly. Readers shouldn’t have to reorder your sentences to follow your reasoning.
One last point. How long should a paragraph be? As long as the context requires—whether that means 15 sentences or only 1. Yes, the occasional one-sentence paragraph is quite permissible. If you’re thinking of word counts, though, a good deal of modern legal writing, at its best, runs to average paragraphs of 100–150 words. That’s about five or six sentences.
But that’s only an average. The fact is that you want variety in paragraph length just as you do in sentence length.
Further reading:
Garner, The Elements of Legal Style 62–66 (2d ed. 2002).
Garner’s Modern English Usage 1059 (5th ed. 2022).
Garner, Legal Writing in Plain English § 26, at 88–91 (2d ed. 2013).
Garner, The Winning Brief 155–60 (3d ed. 2014).
Scalia & Garner, Making Your Case 109–11 (2008).