Sadly the truth is alot of these major banks have been caught in money laundering schemes with some of these large drug organizations (not just mexican cartels) multiple times. The dollar bill will always rain supreme in the eyes of man, don't see anything in the near future changing that, we might even see things worsening with the current economic collapse.
Two of the banks most notable in these schemes are HSBC and wells fargo, but does not mean these are the only two involved in illegal activities.
Add credit suisse to that list