This is not a new story, but super slayer Matt Taibbi is out in Rolling Stone with this story on the Interest Rate Swap scam in Jefferson County.
How can this happen? What is happening on the books of the bank to account for the disbursement of those fees? People in power had to know. What did they know? When did they know it? Who paid the price and who skated? What was the culture their senior managers put on them, what carrots, what sticks? How might that compare to the carrots and sticks in your world?