I think as long as HubPages can't find the duplicate, then you're fine. A search is performed each time you publish a hub, looking for an exact duplicate of the words you posted. If it finds a match anywhere on the internet, your hub gets flagged. Whether or not you own the rights to the article is irrelevant; HubPages wants original content and a duplicate tag will hurt your presence here. If, however, that newspaper article was never posted online, then you can probably publish it without any penalties.