Despite all of the I.R.S.’s efforts, wealthy American tax cheats are still able to hide their money because Swiss banks are still eager to help them.

An indictment disclosed earlier this month by the United States attorney in Manhattan noted that when the Swiss bank UBS — under strong pressure from Washington — abandoned the secret account business, one of its bankers left, taking with him several clients for whom he then opened secret accounts at five other Swiss banks. Another indictment claims that a Swiss financial adviser who managed secret funds for American clients moved accounts from UBS to two private Swiss banks.

Both advisers are accused of using shady tactics, like opening phony businesses in Hong Kong and fake foundations in Liechtenstein to conceal the money from the Internal Revenue Service. The banks, which are not named in the indictments, were not accused in the fraud because the advisers gave them false documents stating that the account owners were not American. But the banks did have information that could have alerted them to the accounts’ ownership had they done better due diligence.

These indictments follow the disclosure by Credit Suisse that it was the target of a criminal investigation by the Justice Department into how Swiss institutions assisted American income tax evaders. The cases underscore how deeply Swiss banks rely on tax evasion.