The FBI has been repeatedly caught with their hands in the cookie jar.
http://www.floridabulldog.org/2016/06/u-s-attorneys-office-f...
http://www.mintpressnews.com/fbi-planted-bugs-california-cou...
When caught they feign a mixture of complete denial, ignorance, and "I didn't know it was illegal", and they are approximately never held personally responsible by judges.