I happened to see the other day this notice taped to the front door of a store I was about to enter: Due to local ordinance, anyone entering this establishment must be wearing a mask. Aside from the irony that we now want customers to wear masks when only a few months ago, stores, and particularly banks, would not have relished the idea, the phrase due to presents a grammatical knot we should probably untie.
English grammars and usage manuals have long pointed out that the word due is principally an adjective meaning owed or owning or ascribable, and these guides, or at least the more traditional among them, have objected when due is deployed to carry out the function of a preposition or conjunction. Adjectives, as we know, modify nouns or pronouns, but in the sentence we are considering, what exactly is the word that due is describing? We might suspect anyone, a pronoun that could next attract an adjective, but what could it mean to say that anyone was due to local ordinance?
What in fact is going on here is that due, or really the phrase due to, is being used as a preposition, with ordinance as its object. The sentence, then, is beginning with a prepositional phrase, and that phrase is carrying out the work of an adverb. One of the many functions of an adverb is to describe the circumstances in which an action is occurring (which is very close to saying the causes of some happening), and adverbial phrases in English often properly begin a sentence to do just that. So the author of the notice wants us to understand that it is because of a local ordinance that anyone entering the store must be wearing a mask.
But the word due is not a preposition, and therein lies the trouble of the entire matter for the more conserving (or preserving) guardians of the language. The more insightful of these conservators are not so much troubled by the grammatical twist as they are by the rhetorical distance that this use of the phrase due to creates. Compare the phrase due to local ordinance to the phrase because of a local ordinance; the latter is what we would say in a natural way when talking to someone else, and the former sounds more like the written language of a contract or statute. Most likely, a statutory ambiance was in the mind of the writer, given the circumstances that occasioned the notice, but the grammatical construction doubles down on the arresting, legal tone (note, too, the high-toned establishment instead of the more common store), and suggests a customer up against the law rather than a citizen working with other citizens for the common good. The subtext of because of a local ordinance is and of course we all must follow the laws together; the implicit meaning of due to a local ordinance is do it or we’ll call the police.
And so how to revise the original? Because of a local ordinance, anyone entering this store must be wearing a mask would establish a more natural diction by showing cause but presuming cooperation as well. Questions of grammar go hand in hand with matters of rhetoric, the effect our language has on others. Which is why grammar is really a far cry from an antiquarian’s delight. Our grammatical constructions and their rhetorical consequences betray our assumptions, and the more conscious we can become of our assumptions, the more aware we can become of our own personal influence on others.