But hey, auto-saving history without prompting you is worth it, right? (Also figuring out what to advertise to a user.)
http://gizmodo.com/349308/verizon-att-respect-your-sms-priva...
That question has a complex answer. In short: not really.
Unfortunately, I know a little too much about phone networks to have a representative answer. I know very little about Facebook, except that its users usually attribute to it more privacy than it really offers. Trying to understand why that is is the reason for my question.
1) The communications were inadvertently obtained and 2) The communication appears to pertain to commission of a crime.
I don't think you can classify this as inadvertent. So I wonder if Facebook can be sued.
There is one way to find out. Create a decoy post, hear from law enforcement, and sue Facebook.