Seeing as the banks are getting the money a way must be devised to somehow punish them for the mess they have created. Filing criminal charges and going through the courts would probably fail as the really guilty could afford the best defense and after 10 years of enriching the barristers probably only a few junior clerks would get convicted.
So instead I propose decimation.
Every banker/lender/broker (whatever your having yourself) should be lined up.
Every tenth banker singled out and then beaten to death with clubs by the preceding nine in the line.
I'm pretty confident the surviving banks would be more careful in future as a result plus it would make everyone feel better.