Maybe this is an example of how I can't find subjects on Wikipedia, but I'd rather be proved clueless than right in this case.
I just stumbled across a copyvio notice on the article [[1868 Expedition to Abyssinia]] which, after examining the evidence with care, I felt was a case of an editor paraphrasing the text of a source far enough to argue that copyright no longer applied; however, the question whether this was plagiarism remained.
So, attempting to be a good little editor, I began to track down what Wikipedia's policy about plagiarism was (beyond my assumption that it was bad), & after a good-faith search (primarily looking at links to [[Plagiarism]] from articles in the Wikipedia namespace -- which is where policy statements usually live) discovered only two mentions about plagiarism:
* [[Wikipedia:Copyrights]], where it is discussed in a way to suggest it is not a copyright violation; & * [[Wikipedia:Your first article]], where it is mentioned in a discussion of providing one's sources.
While this may appear to some as a case of Wikilawyering or [[instruction creep]], I feel it is a serious omission in our list of policies. I hope I'm not alone in saying that I don't want to find any instances of plagiarism in Wikipedia. However, I don't want to find this sort of thing creeping into Wikipedia under the defense "It's not a copyright violation, it's plagiarism", nor do I want unattributed paraphrases of sources being sent to VfD, either speedy or regular, when a simple acknowledgement of sources might solve the problem. And this is a case clearly different than the "Cite sources" policy currently is, which is intended to handle things like adding controversial material without attributing them to a source.
It'd be nice to have some kind of Cleanup tag applied to force the contributor to improve the language &/or supply the source for the text -- but articles have languished on Cleanup for months or years without being fixed.
But I'm willing to live with whatever the consensus is to handle this problem -- even if it is to treat all suspected cases as a copyvio. It's not that I'm asking for an easy solution here (the issue of how much paraphrase is needed in this case clearly pre-empts that), but a sense of what the community consensus is when (& sadly, not "if") I have to fight this problem.
Geoff