FBI general counsel Valerie E. Caproni, as quoted in today’s New York Times piece on the bureau’s self-accorded new surveillance powers:

“Every one of these has been carefully looked at and considered against the backdrop of why do the employees need to be able to do it, what are the possible risks and what are the controls,” she said, portraying the modifications to the rules as “more like fine-tuning than major changes.”

Of interest here is the part-colloquial, part-corporatese use of auxiliary inversion in the embedded interrogative complement of the backdrop of: instead of the expected why the employees need to be able to do it, what the possible risks are and what the controls are, we get variants that contain subject–auxiliary inversion of the sort normally confined to matrix interrogatives.

Apart from lending Caproni’s speech a PowerPoint-y undertone, the embedded auxiliary inversion has a marked hedging effect, especially in the first conjunct. Why presupposes the truth of the clause from which it is extracted, a characteristic that contributes to the rhetorical effectiveness of questions like Why do you hate America? In an ordinary prepositional-phrase complement of a noun, without subject–aux inversion, an embedded interrogative with why conveys this presupposition quite forcefully: the noun phrase the backdrop of why the employees need to be able to do it forecloses any possibility that the employees might not need to be able to do it. By contrast, Caproni’s inverted variant has the (perhaps unintended) effect of reading like a direct question. While it may nudge the listener toward accommodating the presupposition that the employees need to be able to do it, it also challenges the reasoning that led to that particular shared assumption. Caproni’s rhetorical purpose is undermined by her syntax: instead of putting the need for broader surveillance powers squarely into the realm of the presupposed, her embedded subject–aux inversion pulls it back toward the contested ground of at-issue content.

(For an authoritative overview of the present state of linguistic thought on presupposition, see the recent entry by David Beaver and Bart Geurts in the always excellent Stanford Encyclopedia of Philosophy.)