to put someone on blast
to make someone's shortcomings public
This person is usually an attention seeking asshole that needs to be slapped. The reason for telling is not to be informative but rather to cause trouble
"Thanks for cleaning the kitchen Sarah." "Sarah didnt clean it, I did." "Why did you sirene on me?!"
"What's wrong with John." "He's fine! Just feeling a little guilty because he's cheating on you" "That may be the case but at least he's not a fucking sirene!"