Deep Throat: "No, I have to do this my way. You tell me what you know, and I'll confirm. I'll keep you in the right direction if I can, but that's all. Just... follow the money".

The trail of money will usually confirm where a crime has been, or is about to be, committed.

Take for instance former Illinois Governor Rod Blagojevich when he stated

the state will suspend business with Bank of America Corp. until the lender restores credit to the shuttered Republic Windows & Doors company in Chicago where workers are staging a sit-in.

Having crossed BofA the next day his scandal broke (midtowng posted a very good article on this)

Who is the bankers bank? The Federal Reserve. And who is the latest person to cross the bankers bank? Ken Lewis.