Originally Posted by SimonDoom
My understanding, although I haven't done this, is that as a member you can delete other people's comments to your story, whether they are anonymous or not, but once you've posted a comment to someone else's story you cannot delete it.
Yes, an author can delete any comment in their own story file, but once a comment is posted, that's it, the original commenter cannot edit or remove it. Laurel can remove any comment, any time, and does so against trolls or where accounts are shut down - offensive comments or spam being removed across the whole library.
I have also seen cases where a story's metadata indicates there are comments, but none are shown. I assume this is where an author at first allowed comments, but subsequently turned them off.