A reader asked me yesterday regarding Breaking Bad why Walter White can't just solve his problems by taking his money to a Swiss bank or the Cayman Islands or some such. If you don't watch the show, I think I can reveal without spoilers that the basic setup is White winds up with a heaping pile of cash obtained through illegal means and is facing a logistical problem regarding how to make the cash available to his family after his death.
I sort of regret that the show doesn't explicitly address the Swiss banking issue, because I was once in Switzerland and talking to a private banker there who complained to me that Americans have a lot of Hollywood-driven misconceptions about Swiss banking. Americans, he said, tend to think of banking secrecy as all about money laundering for terrorists or drug traffickers when the real truth is that it's mostly for rich people trying to avoid taxes or husbands trying to shield assets from their wives during divorce proceedings.
The basic issue is that even with "offshore" banks you can't just show up with an oil drum full of cash and no explanation. The bank is going to ask you for some kind of documentation of how you earned the money.
One important reason for that historically has precisely been able to preserve their function as havens for tax evasion and asset-shielding. Neither Switzerland nor the Cayman Islands nor any other offshore banking center is exactly a mighty superpower. Their ability to preserve banking secrecy is based largely on the acquiescence of the world's major powers. And elites in the United States, United Kingdom, Germany, France, etc. are a lot more likely to wink and nod at tax avoiders than at major drug drealers and mass murderers. Letting too many violent criminals in the door would risk spoiling the whole party. And in recent years the party's largely been spoiled anyway. Some 2009 charges the American government brought against UBS have greatly increased the amount of information sharing that Swiss banks do with the American government. The European Union has also ganged up on Switzerland in the past few years and made them crack down on tax avoiders. The Caymans have gone the same way.