Always funny how Slashdot uses the "silenced person" icon.
Meanwhile, they have a site where the "anonymous coward" can log in to a duplicate account and mod posts down against a commenter they don't agree with until that commenter is literally slienced beyond one or two pre-modded -1 comments a day.
The downvotes are fairly predictable: anyone who doesn't toe the scientism line or who doesn't agree with the fundamentalist atheist dogma is usually first to be mass downvoted. Often a simple declarative sentence is all it takes to rile up some greasy neckbeard asshole, who will dump all five mod points into retaliating because greasy neckbeard assholes take declarative statements as a personal insult.
If you reply, that just gives their duplicate account another three-point shot at your "karma," which is simply a measure of how well you agree with the Slashdot party line. All the greasy neckbeard asshole wants is grist for his logic mill so he can "disprove" everything you say by downvoting it and labeling it.
So essentially, Slashdot is simply a machine to enforce groupthink. Nobody is allowed to color outside the lines without being chased away by the downvotes. It's very much like Boingboing, which is a site devoted to enforcing Cory Doctorow's personal prejudices and cowardly bigotry through his proxy mods.
I propose this be fixed before you spend any more time on your big beta project.
tl;dr Slashdot's moderation system does nothing but force commenters to say the "right thing(tm)"