Libor scandal
The banks are supposed to submit the actual interest rates they are paying, or would expect to pay, for borrowing from other banks. The Libor is supposed to be the total assessment of the health of the financial system because if the banks being polled feel confident about the state of things, they report a low number and if the member banks feel a low degree of confidence in the financial system, they report a higher interest rate number. In June 2012, multiple criminal settlements by Barclays Bank revealed significant fraud and collusion by member banks connected to the rate submissions, leading to the scandal.