Glenn Bingham send in a link to this passage in a recent radio address by Paul LePage, the governor of Maine ("Obamacare is on Hold in Maine", 7/7/2012):
Even more disheartening is that reviving the American dream just became nearly impossible to do. We are now a nation in which supports dependency rather than independence. Instead of encouraging self-reliance we are encouraging people to rely on the government.
Without the audio, I would have guessed that this was an editing mistake, where perhaps the speechwriter started with a different construction (e.g. "a nation in which dependency is encouraged"), and then changed the structure of the relative clause without changing the transition to it. Even with the audio, I'd lean towards that analysis. But Glenn writes:
This is the third time I have heard this orally, but it has become the standard in written English among my students in Mid-Atlantic US.
By "it" he means the use of superfluous (or at least nominally ungrammatical) pre-which prepositions — and he gives many examples from his students' compositions:
Also let's not forget the atmosphere in which we live in.
The basic aim of moral philosophy is to come up with a standard principle on which all moral judgments are based on.
For this assignment, I chose unicorns to be my mythological character in which I am familiar with.
It is an entity in which all things came from and will come from.
Conversely, hypothetical imperatives state that there is a particular goal for which we act on.
In today's society, it seems as though there has been a large difference in the moral standards of the future generations compared to those in which many of us were raised with ourselves.
Thales believed that the substance out of which all living things came from was water.
We discussed such extra prepositions a few years ago ("A phenomenon in which I'm starting to believe in", 5/14/2007). As David Dennison and Nuria Yáñez-Bouza explained, they've been around at least since Middle English ("Back to the future, redundant preposition department", 5/4/2007); but the apparent lack of common spoken-language examples makes it seem unlikely that the flowering of such constructions in apprentice writing is a vernacular survival.
But Glenn's example from Governor LePage raises another question. Is this an isolated, perhaps careless, mistake by an over-caffeinated speechwriter? Or is it the leading edge of a new development, where extra semantically-associated prepositions are added to clause-initial relative pronouns, even when no preposition would normally appear in the relevant place in the relativized clause?
Glenn gives one student-writing example that seems to be of this type:
Empiricists believe that the mind, upon its creation, is a “blank slate” for which we fill up through our experiences and senses.
Can readers supply others? Will David and Nuria show us that this sort of thing was common in Chaucer? Are there in fact related phenomena in varieties of spoken English?
Or is this a sort of constructional hypercorrection, in which apprentice writers, unfamiliar with the grammar of un-stranded prepositions, develop some peculiar hypotheses about how the formal written language handles such things? That was my first reaction ("A note of dignity or austerity", 5/3/2007), but now I'm not so sure.
Update — here are some other perhaps-relevant examples from Gov. LePage's Weekly Radio Addresses:
Creating a sound, predictable business climate is what my administration has been focused on. Streamlining rules and regulations, including the permitting process in which our job creators must adhere by, is a step every department is taking seriously. [9/17/2011]
It is a time to think about the values in which our great Nation was built upon and reflecting on the direction our Nation is headed in. [8/6/2011]