Style: Passive Voice

Here's an example from the "Channeling" memo of the Selective Service (1965), describing how certain men in scientific and technological jobs receive deferments, while others are "channeled" into the military:

This deferment is accomplished on the basis of evidence of record in each individual case. No group deferments are permitted. Deferments are granted, however, in a realistic atmosphere so that the fullest effect of channeling will be felt, rather than be terminated by military service at too early a time.

Here the passive voice permits the Selective Service Board to hide behind impersonal language. Passive voice is the language of the done-to; 

A registrar reading this memo would not know who was doing what to whom, only that some vast bureaucratic process was at work which might draft him.

Sometimes the language of the done-to is useful:

The Vietnam memorial bears the names of those who were killed in the war. The houses were covered in snow up to the windows.

More often, the active voice helps illustrate the agent and the effects of action.

Lucy was bitten by the vampire and transformed into a vamp.
The vampire bit Lucy, transforming her into a vamp.

It was arranged that Senator Flugelhorn be summoned before the subcommittee to answer certain charges which had been brought against him by his former aides.

The subcommittee summoned Senator Flugelhorn to answer charges made by his former aides.

   Passive Voice
   Intransitive Verbs
   Too Many Little Words
   Adverbitis
   Hitchhikers, Babblers, and Jaw-Flappers
   Windy and Pretentious Language
   Balance and Consistency