Or any of the others who work on the code. However, even jacquesm[0] - third on the leader board[1] - says that to the best of his knowledge one cannot downvote articles:
There are no downvotes on stories, unless you consider flagging a kind of story downvote. That's a legitimate way to look at it, since it answers the complaint upthread [1]: if you think that a story is not appropriate for HN, that's what flagging is for.
[1] https://news.ycombinator.com/leaders