There seems to be an issue with questions being closed as duplicates when they are not. Often times just because titles are similar doesn't mean the entire question is the same. Here's one example and another.
Is there any system in place for reopening closed questions, aside from casting an open vote? I was thinking it may be good to sometimes give users the option to veto a reopen, for example once a week a user can reopen a "marked as duplicate" question of there's. If the question really was a duplicate then the user would gain nothing my reopening it, so it seems unlikely the system would be abused.