EDIT: Having read the CSO's explanation that the guy was using his company work email, it makes more sense why the CSO would contact the company (and explains away the pettiness my comment was referring to)

One thing I notice: if the CSO felt like this person did something grossly illegal and irresponsible, why not go straight to the police? Why instead go to the man's employer and speak passively aggressively?

Paradoxically, contacting the authorities could have helped facebook's argument. It would communicated to the community at large: "Hey Facebook believes it has clear standing to pursue this guy. Maybe, he really did do something wrong."

Instead, what I'm reading is: "Facebook doesn't actually believe what the guy did was illegal per se... but they wanted to spite the guy anyway."

For me, it seems petty.