Much editing consists of changing passive to active, but — if active voice is more direct, simple, and natural, as often claimed — why does the untutored writer naturally use the passive? Understanding the reason a tendency exists is part of controlling it; understanding helps discount or modify our writing instincts, but I've seen no explanations of the passive voice's pervasiveness in much bad writing.
Untutored writers overuse the passive voice because the passive word order corresponds to the events' order in knowledge acquisition. Temporal beings, we are stuck in the present: only present events impinge on us directly. From our present perceptions we mentally reconstruct the past and project the future. When we rely on memory, the rememberings pertaining to the past occur in the present. From memory traces in the present, we figure out what happened in the past, whether we accomplish this reconstruction consciously or unconsciously.
The passive voice, which starts by positing current perception, mirrors our path to knowledge. To transform the passive to active, we must carry our starting point in working memory, instead of writing our thoughts as they occur. Active voice isn't more direct, not when we are reporting our thought processes leading to a conclusion, and in documents concerned with the process of discovery, as in reports of scientific experiments, the appropriateness of the passive is recognized by everyone but a few plain-English exponents. A simple example shows how the passive voice mirrors the knowledge-acquisition process:
The Jacksons's house was wrecked.
To acquire this information directly, we look at the house, and this we can do only in the present, despite the vandalism's occurring in the past. From the perception of the wrecked house in the present, we infer that it was wrecked in the past. The natural way to record our thought process is first to posit the house and then the results of our inspection. To make it active, "A vandal wrecked the Jacksons's house," we must start with a distant result of our inference, carrying the starting point in memory.
Now a more complicated legal example (from Bryan Garner's The Winning Brief, Tip 30, Example B, p. 159):
To support a trespass action when the injurious acts complained of were not actually committed by the defendant himself, the person who committed the acts must be either employed, paid, or controlled by the defendant in order to hold him liable.
(Garner rewrites this sentence "For the defendant to be liable in a trespass action when the defendant did not personally commit the acts complained of, the defendant must have employed, paid, or controlled the person who committed the acts.")
The lawyer starts from perception of the complaint's allegations of injurious acts and, by reasoning from the complaint's language, deduces that the defendant didn't commit them. The lawyer then proceeds to look for agency allegations regarding the trespassing person. The natural and direct way to record this analysis starts with the "injurious acts complained of," creating a passive-voice construction.
If the active voice isn't a more direct report of our thoughts, what recommends its use? The basic reason is the passive-voice's verbosity. The flabbiness of passive-voice writing comes not from its lack of directness or naturalness but from an excess of verbiage compared to the more concise active voice. The guideline to favor active over passive quests for Concision.