Banks are often unwitting enablers of financial crime , but at the same time , they are our strongest defense against financial crime as gatekeepers of the financial system . Regulators hold banks accountable for complying with ever-increasing and complex regulatory requirements . For example , in the face of the tsunami of sanctions packages unleashed against Russia by the European Union ( EU ), U . S . and U . K . in response to the war in Ukraine , banks had to take risk-based preventative measures to comply with the myriad complex requirements .