I see the user guide above, but does Civil offer any advice on what should be flagged? I see three options in Flag: "abuse/harassment, spam or threat to self or others". Those last two are fairly clear, but I can imagine disagreement on the first. I'd be interested in which of the comments below rises to abuse/harassment and I imagine there is disagreement within commenters. 

A. "This is a horrible idea".
B. "This is the dumbest idea I've ever heard of and anyone who supports it is doesn't understand the underlying issues".
C. "Anyone who supports this awful idea is ignorant".
D. "Anyone who supports this awful idea is an idiot"
E. "I can't believe you support this idea- you must be an idiot".