The FBI exists to justify itself. An up-front, moralizing tone is reassuring to non-technically literate people who don't realize this is equivalent to tracing all of our most intimate conversations.
As it sounds like it was social engineering [e.g. Getting into the private/admin areas of the forum via an undercover agent] I'm not sure you can state that.
Sorry, I meant it in terms of the ominous "nobody is safe behind a keyboard"—not only do they seem to be proud to be so invasive, but they're even adopting a moralizing tone.
