Almost everyone was taught in school to avoid using the passive voice. Fewer know how to identify the passive voice, but I'm going to assume for the moment that you are part of the elite who can and ask you to do a little grammatical analysis with me.

One locus classicus deploring the passive is George Orwell's essay "Politics and the English Language". It comes in the midst of Orwell's list of strategies "by means of which the work of prose construction is habitually dodged":

In addition, the passive voice is wherever possible used in preference to the active, and noun constructions are used instead of gerunds (by examination of instead of by examining).

Do you notice anything ironic about Orwell's phrasing here?

That's right. Orwell uses the passive voice in the very moment that he condemns it.

This almost sounds like one of those lists of grammatical faults that exemplify the faults they prohibit. Is it conscious irony? Possibly, but I doubt it. For one thing, Orwell's tone throughout the essay is not particularly self-deprecatory. For another, this "is used" is only one of a series of passive-voice constructions that appear throughout this part of the essay. Orwell frequently uses the passive when the passive is not under discussion.

Here is the larger context in which the above quotations appear. I have emphasized the passives so you can see the pattern. (NB, when adverbs fall between the passive auxiliary and the past participle, I've left them highlighted for simplicity's sake, but of course they're not part of the passive construction itself. To be conservative, I'm also not counting past participial phrases that function as modifiers as passive, although they are derived from passive constructions.):

Each of these passages has faults of its own, but, quite apart from avoidable ugliness, two qualities are common to all of them. The first is staleness of imagery; the other is lack of precision. The writer either has a meaning and cannot express it, or he inadvertently says something else, or he is almost indifferent as to whether his words mean anything or not. This mixture of vagueness and sheer incompetence is the most marked characteristic of modern English prose, and especially of any kind of political writing. As soon as certain topics are raised, the concrete melts into the abstract and no one seems able to think of turns of speech that are not hackneyed: prose consists less and less of words chosen for the sake of their meaning, and more and more of phrases tacked together like the sections of a prefabricated henhouse. I list below, with notes and examples, various of the tricks by means of which the work of prose construction is habitually dodged:

Dying Metaphors
A newly invented metaphor assists thought by evoking a visual image, while on the other hand a metaphor which is technically "dead" (e.g. iron resolution) has in effect reverted to being an ordinary word and can generally be used without loss of vividness. But in between these two classes there is a huge dump of worn-out metaphors which have lost all evocative power and are merely used because they save people the trouble of inventing phrases for themselves. Examples are: Ring the changes on, take up the cudgel for, toe the line, ride roughshod over, stand shoulder to shoulder with, play into the hands of, no axe to grind, grist to the mill, fishing in troubled waters, on the order of the day, Achilles' heel, swan song, hotbed. Many of these are used without knowledge of their meaning (what is a "rift," for instance?), and incompatible metaphors are frequently mixed, a sure sign that the writer is not interested in what he is saying. Some metaphors now current have been twisted out of their original meaning withouth those who use them even being aware of the fact. For example, toe the line is sometimes written as tow the line. Another example is the hammer and the anvil, now always used with the implication that the anvil gets the worst of it. In real life it is always the anvil that breaks the hammer, never the other way about: a writer who stopped to think what he was saying would avoid perverting the original phrase.

Operators or Verbal False Limbs
These save the trouble of picking out appropriate verbs and nouns, and at the same time pad each sentence with extra syllables which give it an appearance of symmetry. Characteristic phrases are render inoperative, militate against, make contact with, be subjected to, give rise to, give grounds for, have the effect of, play a leading part (role) in, make itself felt, take effect, exhibit a tendency to, serve the purpose of, etc., etc. The keynote is the elimination of simple verbs. Instead of being a single word, such as break, stop, spoil, mend, kill, a verb becomes a phrase, made up of a noun or adjective tacked on to some general-purpose verb such as prove, serve, form, play, render. In addition, the passive voice is wherever possible used in preference to the active, and noun constructions are used instead of gerunds (by examination of instead of by examining). The range of verbs is further cut down by means of the -ize and de- formations, and the banal statements are given an appearance of profundity by means of the not un- formation. Simple conjunctions and prepositions are replaced by such phrases as with respect to, having regard to, the fact that, by dint of, in view of, in the interests of, on the hypothesis that; and the ends of sentences are saved from anticlimax by such resounding commonplaces as greatly to be desired, cannot be left out of account, a development to be expected in the near future, deserving of serious consideration, brought to a satisfactory conclusion, and so on and so forth.

Pretentious Diction
Words like phenomenon, element, individual (as noun), objective, categorical, effective, virtual, basic, primary, promote, constitute, exhibit, exploit, utilize, eliminate, liquidate, are used to dress up a simple statement and give an air of scientific impartiality to biased judgements. Adjectives like epoch-making, epic, historic, unforgettable, triumphant, age-old, inevitable, inexorable, veritable, are used to dignify the sordid process of international politics, while writing that aims at glorifying war usually takes on an archaic color, its characteristic words being: realm, throne, chariot, mailed fist, trident, sword, shield, buckler, banner, jackboot, clarion. Foreign words and expressions such as cul de sac, ancien regime, deus ex machina, mutatis mutandis, status quo, gleichschaltung, weltanschauung, are used to give an air of culture and elegance. Except for the useful abbreviations i.e., e.g., and etc., there is no real need for any of the hundreds of foreign phrases now current in the English language. Bad writers, and especially scientific, political, and sociological writers, are nearly always haunted by the notion that Latin or Greek words are grander than Saxon ones, and unnecessary words like expedite, ameliorate, predict, extraneous, deracinated, clandestine, subaqueous, and hundreds of others constantly gain ground from their Anglo-Saxon numbers. The jargon peculiar to Marxist writing (hyena, hangman, cannibal, petty bourgeois, these gentry, lackey, flunkey, mad dog, White Guard, etc.) consists largely of words translated from Russian, German, or French; but the normal way of coining a new word is to use Latin or Greek root with the appropriate affix and, where necessary, the -ize formation. It is often easier to make up words of this kind (deregionalize, impermissible, extramarital, nonfragmentary and so forth) than to think up the English words that will cover one's meaning. The result, in general, is an increase in slovenliness and vagueness.

Meaningless Words
In certain kinds of writing, particularly in art criticism and literary criticism, it is normal to come across long passages which are almost completely lacking in meaning. Words like romantic, plastic, values, human, dead, sentimental, natural, vitality, as used in art criticism, are strictly meaningless, in the sense that they not only do not point to any discoverable object, but are hardly ever expected to do so by the reader. When one critic writes, "The outstanding feature of Mr. X's work is its living quality," while another writes, "The immediately striking thing about Mr. X's work is its peculiar deadness," the reader accepts this as a simple difference opinion. If words like black and white were involved, instead of the jargon words dead and living, he would see at once that language was being used in an improper way. Many political words are similarly abused. The word Fascism has now no meaning except in so far as it signifies "something not desirable." The words democracy, socialism, freedom, patriotic, realistic, justice have each of them several different meanings which cannot be reconciled with one another. In the case of a word like democracy, not only is there no agreed definition, but the attempt to make one is resisted from all sides. It is almost universally felt that when we call a country democratic we are praising it: consequently the defenders of every kind of regime claim that it is a democracy, and fear that they might have to stop using that word if it were tied down to any one meaning. Words of this kind are often used in a consciously dishonest way. That is, the person who uses them has his own private definition, but allows his hearer to think he means something quite different. Statements like Marshal Pétain was a true patriot, The Soviet press is the freest in the world, The Catholic Church is opposed to persecution, are almost always made with intent to deceive. Other words used in variable meanings, in most cases more or less dishonestly, are: class, totalitarian, science, progressive, reactionary, bourgeois, equality.

If the irony were intentional, you would expect Orwell to employ the active everywhere except in the moment of singling out the passive. Instead, it is sprinkled throughout. Further, he does not engage in self-parody by using the other verbal ticks that he condemns.

Generations of composition teachers have assigned this essay to their students. How many, I wonder, have actually noticed just how pervasive the passive is in this section? If they do not notice, there is an irony there almost as strong as that in the text itself. If they do notice, the passage can be a productive starting point for a discussion on how the passive can be used appropriately. For there really isn't anything wrong with the way Orwell uses the passive. It makes perfect sense in context.

One of the principal functions of the passive is to control the focus of the sentence. By shifting between active and passive voice, we choose what what noun phrase appears in the subject. Since the subject is also commonly the first element in a sentence, this procedure by extension gives us a way to maintain the appropriate topic. (The opening of a sentence, whether it's the grammatical subject or not, typically establishes the topic--the rest of the sentence then adds new information about the topic.)

Notice the string of subjects that go with all these passive verbs. They all concern words and closely related topics (metaphors, etc.). And that, after all, it Orwell's topic in this section: the language, and not the writers. Thus the passive voice here is a natural and appropriate outgrowth of Orwell's focus. To rewrite all these sentences in the active is certainly possible, in most cases, but it would shift the emphasis in ways that are arguably inappropriate.

And in a few cases, we could not eliminate the passive without serious damage. For example:

"Words like romantic...are strictly meaningless, in the sense that they not only do not point to any discoverable object, but are hardly ever expected to do so by the reader."

If we were to take the second predicate and rewrite it in the active without making any other changes, we would get a truly awkward sentence:

"Words like romantic...are strictly meaningless, in the sense that they not only do not point to any discoverable object, but the reader hardly ever expects then to do so."

The rewritten version is now unparallel. Even if we fix that, for example with

"Words like romantic...are strictly meaningless, in the sense not only that they do not point to any discoverable object, but that the reader hardly ever expects then to do so."

the sentence still shifts topics abruptly and for no good reason, from words to the reader. That shift hurts the conceptual unity of the sentence.

The lesson for teachers: the Strunk and White proscription of the passive voice is asinine, and by laying down draconian rules to your students that forbid its use in all contexts, you are doing your students a grave disservice.

Many instances of the passive voice are objectionable, true, but then so are many instances of the active voice. The issue cannot be decided simply by looking at the grammatical form in isolation. You must understand the larger context in which the phrasing appears.

Some teachers argue that the passive is fine for advanced writers but that beginning writers should avoid it because of its potential difficulty. I find this argument specious. Teach your students how to control the ideas in a paragraph. Teach them how to manage the flow of information smoothly, moving from old information to new. Teach them how to manipulate their sentence structure so they can shift from active to passive and back with ease. With those concepts in place, the choice of active or passive voice will fall out naturally from the context. Their use of the passive will be as unnoticed and unobjectionable as it is in Orwell's essay.

Note: The basic observation about Orwell is not original to me. It was made over 25 years ago by Joseph Williams in "The Phenomenology of Error," College Composition and Communication 32 (1981): 152-68.