When Prentiss breaks the glass window with her elbow, Paget Brewster actually cut herself. She got excited by this and was showing her "war wound" to everyone.
It is mentioned that Baker, one of the thrill killers from Hopeless (2009), had been tried and found guilty. His two accomplices committed suicide by cop at the end of the aforementioned episode.
An actual case quite similar to this one happened in 1999 in Texas, several prostitutes were murdered and had their eyes removed.