It seems like a mix of Reddit google's network algorithm could work - don't just upvote/downvote the post, but lend the commenter's credibility. So upvotes from hordes of poo-flinging monkeys aren't weighted as heavily from upvotes from credible sources.
Then the hack: this is a newspaper. They have no reason to be fair. Give community moderators super-credibility. So they can upvote people and not just give their comment visibility, but by upvoting they incidentally give them credibility for future comments. And in turn, those commenters' upvotes are more powerful as well, thanks to the credibility lent by the community mods.
It creates an echo-chamber, of course... but ultimately, that's what people want.
Then the hack: this is a newspaper. They have no reason to be fair. Give community moderators super-credibility. So they can upvote people and not just give their comment visibility, but by upvoting they incidentally give them credibility for future comments. And in turn, those commenters' upvotes are more powerful as well, thanks to the credibility lent by the community mods.
It creates an echo-chamber, of course... but ultimately, that's what people want.