I don't understand why law enforcement officials leak this stuff. Presumably they aren't benefitting financially (that would be highly illegal, and surely investigated?), and they aren't ever named publicly, so they don't even get fame out of it. So why risk your job like that?
I used to work in journalism. Half of the journalism empire is built upon looking out for people so they'll look out for you in the future.
It's a minor scene in The Insider, but at one point Al Pacino's real-life character, CBS producer Lowell Bergman, helps the FBI out by not investigating a story. Later, the person he helped at the FBI tips CBS off exclusively about the arrest of the Unibomber, and tells them where to be. I believe that story is at least somewhat based on reality, and I've seen similar ones play out constantly in the media.
"Thank you for the positive coverage on that embarrassing story for the department," and so on, and eventually cops become a fountain of leads.
