Reports are to be written in passive voice

It's report (report cards) time at my school, which usually means long hours and major headaches. Besides writing 100 paragraphs about my own 100 students, I was unanimously selected to be the chief proofreader for the rest of the Social Studies department because I am the only English geek in the bunch who has eagle eyes to search out typos wherever they lurk. So I read about 1,000 more paragraphs. Apologies for being such a grammarian, but in the course of reading all those comments, I couldn't help noticing the Kiwi predilection to write in passive voice.

First, an example of passive voice: The hamburger was eaten by me.
and an example of active voice: I ate the hamburger.
Seemingly, both sentences convey the same information, but there is a different tone to the first one. It's as if the hamburger went out and got itself eaten; as if it was somehow the hamburger's fault. As you can see, the passive voice can be used to shed blame.

What I noticed on reports is a tendency to write things such as: She is to be commended for her effort or It is pleasing for me to see her improvement. Why can't they just say I was pleased with her improvement!?!?

I was wise enough NOT to put red marks all over my fellow teachers' reports every time I saw passive voice. I reserved my red pen for their instead of there, run-on sentences and typos. But I mentioned the preponderance of passive writing to them, who were absolutely shocked to hear that the passive voice is frowned upon in America.

In fact, most American university professors believe that the passive voice signals sloppy, lazy thinking; that the writer has not fully thought through what they are discussing. Automatic grammar-checkers on word processing programs also point out passive construction, as if it needs to be changed.

But in New Zealand, it is accepted and even preferred. The Auckland newspaper is full of sentences like It is understood that the man was from Hamilton. In America, the reporter would have written Unidentified witnesses said... instead.

My colleagues and I agreed that this is a partly due to the British penchant for understatement. Likewise, there is a custom of not wanting to take credit for something for fear of looking like a braggart. Therefore, a NZ company report would say clients were well-served. American culture, however, values directness and speaking plainly. Americans aren't afraid to take credit and a US company report would say: our staff served clients well.

And yet, an American made perhaps one of the more memorable passive statement, used to shed blame: Ronald Reagan said "mistakes were made" when referring to the Iran-Contra scandal.