Although I know the Slashdot moderator policy, which states that comments not related to the story topic should get modded "Offtopic", I am disgruntled how comments criticising story submitters or editors are handled.
Looking at the comment moderations of comments appended to stories submitted by Roland Piquepaille yields quite a sad truth about Slashdot. For information: Piquepaille abuses Slashdot to drive traffic to his blog by submitting stories looking legitimate by letting the first link point to some real news source. The second link though is always described as "providing more details and information", which is a link to his own blog, where he basically only cut&pasted parts of the original story plus some material from other sources (which were linked to from the original story itself). Latest example is " Is This Rembrandt a Real One?"
But back to the comments: critics are always handled by the same procedure. Although they may receive up to +5 mod points during the first 15 minutes or so, they are afterwards systematically modded down to "-1 Offtopic". Since this happens in a period of only 1 or 2 minutes, and there have to be quite a lot of mod points to be burnt, I highly suspect that this is carried out by the editors (which have unlimited mod points), to silence critics. Latest example is a thread consisting of at least 40 comments of which at least 30 were modded either "-1 Offtopic" or "0 Offtopic" at the time of this writing (note that moderation has not been closed up to this point), plus 7 comments which started off as 0 anyways.
It looks like although Slashdot seems to stand up for personal freedoms, the editors simply mute critics of the them.
I wish for 2006 that discussions about editing style and story submitters are handled more open-mindedly, and censorship is not being applied to people who express their views about either the submitter or the editor in charge.