Reasons a post was flagged as abusive?

Is there a way for a regular user to report WHY they are flagging a post as abusive? 

I had a community member flag a post as abusive, but I couldn't figure out why. I reached out to him directly and he confirmed he flagged it as a duplicate. Giving this user that option (versus spam, offensive, etc.) would help me as the moderator narrow down how to review this. I thought I've seen this before, but I can't find an option for it. If not, I'll create an Idea for it.