I'm not well educated in this regard, but my general understanding is that such agencies tend to protect their own. Police men will protect other police men. The CIA will protect employees against crimes they may have committed.

In general, you're only going to have a problem like this if you do something to piss off the rest of your organization. But as long as you conform they are more likely to protect you than turn against you.

Don't snitch. Give unconditional respect to everyone that's a made man or higher in the organization. Follow orders. Don't snitch. Pay your superior their cut of your business. Don't step on anyone else's toes [without getting permission first]. Don't snitch.

The unwritten rules for any corrupt organization are pretty simple. "Keep your mouth shut," is always one of them, and possibly the only unforgivable offense.