Every decent book on legal writing or writing in general advises you to strive for simplicity: short words, easy-to-follow sentence structure, coherent paragraphs, etc. Today, most lawyers probably know that plain language fosters effective communication: the reader is more likely to understand what the writer is trying to say. If the only thing that writing in plain language did were to make the message easier to understand, that would be reason enough to write plainly.
But for lawyers whose business is persuasion, the importance of plain language is more profound. Readers judge the character and intelligence of the lawyers themselves by the quality of their writing. They associate plain language with intelligence and credibility, and they associate foggy, needlessly complicated writing with a lack of intelligence and credibility.
This fact was shown years ago in a study by Robert W. Benson and Joan Kessler, Legalese v. Plain English: An Empirical Study of Persuasion and Credibility in Appellate Brief Writing, 20 Loy. L.A. L. Rev. 301 (1987). In their study, they asked judges and court staff attorneys to rate two versions of the same paragraph: one in legalese and the other in plain English. The readers tended to rate the legalese version as unconvincing and unpersuasive. They also tended to rate the authors of the legalese passages as being ineffective advocates from non-prestigious law firms. In other words, they formed opinions about not only the writing, but about the credibility of the author.
A 2006 study by psychologist Daniel M. Oppenheimer confirmed that readers tend to negatively evaluate the authors of needlessly complicating text. Consequences of Erudite Vernacular Utilized Irrespective of Necessity: Problems with Using Long Words Needlessly, 20 Applied Cognitive Psychology 139 (2006). In this study, groups of readers were given different versions of various writings, one in simple language and the other in more complicated language. The readers consistently rated the writers of the more complicated version as less intelligent. Oppenheimer’s conclusion: “write clearly and simply if you can, and you’ll be more likely to be thought of as intelligent.”
Why are plain-language writers thought of more highly than writers of needlessly complicated language? Oppenheimer’s study suggests that the answer is in “processing fluency. Simpler writing is easier to process, and studies have demonstrated that processing fluency is associated with a variety of positive dimensions,” including truth, confidence, and liking. Daniel Kahneman describes the same idea as “cognitive ease,” as opposed to “cognitive strain.” (See my last post.) According to Kahneman, anything that contributes to cognitive ease makes the reader more likely to believe the message and trust the messenger. One thing that can contribute to cognitive ease is plain, simple language. Complicated language has the opposite effect, causing the reader to experience cognitive strain, making the reader more vigilant and suspicious of the message and the messenger.
There’s a link between these modern psychological studies and the ancient writings of Aristotle on persuasion. According to Aristotle, ethos—the character of the speaker—is critical to persuasion. The speaker (or today, the writer) gains the audience’s trust by creating the impression that he or she is a person of intelligence and truthfulness. This impression can be made through the argument itself. E.g., Edward P.J. Corbett and Robert J. Connors, Classical Rhetoric for the Modern Student 19 (4th ed. 1999). The modern-day psychological studies show that plain language builds ethos; it makes the writer appear more intelligent and credible. This, in turn, makes the reader more disposed to accept the argument.